perf: enable WAL mode, batch price lookup, add DB diagnostics to schema_state

- Set PRAGMA journal_mode=WAL + synchronous=NORMAL on SQLite open;
  eliminates read blocking during background pricelist sync writes
- Replace N+1 per-lot price loop in QuoteService local fallback with
  GetLocalPricesForLots batch query (120 queries → 3 per price-levels call)
- Add CountAllPricelistItems, CountComponents, DBFileSizeBytes to LocalDB
- Report local_pricelist_count, pricelist_items_count, components_count,
  db_size_bytes in qt_client_schema_state for performance diagnostics

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bible-local/03-database.md

@@ -29,31 +29,369 @@ Rules:
 
 ## MariaDB
 
-MariaDB is the central sync database.
+MariaDB is the central sync database (`RFQ_LOG`). Final schema as of 2026-03-21.
 
-Runtime read permissions:
-- `lot`
-- `qt_lot_metadata`
-- `qt_categories`
-- `qt_pricelists`
-- `qt_pricelist_items`
-- `stock_log`
-- `qt_partnumber_books`
-- `qt_partnumber_book_items`
+### QuoteForge tables (qt_* and stock_*)
 
-Runtime read/write permissions:
-- `qt_projects`
-- `qt_configurations`
-- `qt_client_schema_state`
-- `qt_pricelist_sync_status`
+Runtime read:
+- `qt_categories` — pricelist categories
+- `qt_lot_metadata` — component metadata, price settings
+- `qt_pricelists` — pricelist headers (source: estimate / warehouse / competitor)
+- `qt_pricelist_items` — pricelist rows
+- `stock_log` — raw supplier price log, source for pricelist generation
+- `stock_ignore_rules` — patterns to skip during stock import
+- `qt_partnumber_books` — partnumber book headers
+- `qt_partnumber_book_items` — PN→LOT catalog payload
+
+Runtime read/write:
+- `qt_projects` — projects
+- `qt_configurations` — configurations
+- `qt_client_schema_state` — per-client sync status and version tracking
+- `qt_pricelist_sync_status` — pricelist sync timestamps per user
 
 Insert-only tracking:
-- `qt_vendor_partnumber_seen`
+- `qt_vendor_partnumber_seen` — vendor partnumbers encountered during sync
+
+Server-side only (not queried by client runtime):
+- `qt_component_usage_stats` — aggregated component popularity stats (written by server jobs)
+- `qt_pricing_alerts` — price anomaly alerts (models exist in Go; feature disabled in runtime)
+- `qt_schema_migrations` — server migration history (applied via `go run ./cmd/qfs -migrate`)
+- `qt_scheduler_runs` — server background job tracking (no Go code references it in this repo)
+
+### Competitor subsystem (server-side only, not used by QuoteForge Go code)
+
+- `qt_competitors` — competitor registry
+- `partnumber_log_competitors` — competitor price log (FK → qt_competitors)
+
+These tables exist in the schema and are maintained by another tool or workflow.
+QuoteForge references competitor pricelists only via `qt_pricelists` (source='competitor').
+
+### Legacy RFQ tables (pre-QuoteForge, no Go code references)
+
+- `lot` — original component registry (data preserved; superseded by `qt_lot_metadata`)
+- `lot_log` — original supplier price log (superseded by `stock_log`)
+- `supplier` — supplier registry (FK target for lot_log and machine_log)
+- `machine` — device model registry
+- `machine_log` — device price/quote log
+
+These tables are retained for historical data. QuoteForge does not read or write them at runtime.
 
 Rules:
-- QuoteForge runtime must not depend on any removed legacy BOM tables;
+- QuoteForge runtime must not depend on any legacy RFQ tables;
 - stock enrichment happens during sync and is persisted into SQLite;
-- normal UI requests must not query MariaDB tables directly.
+- normal UI requests must not query MariaDB tables directly;
+- `qt_client_local_migrations` was removed from the schema on 2026-03-21 (was in earlier drafts).
+
+## MariaDB Table Structures
+
+Full column reference as of 2026-03-21 (`RFQ_LOG` final schema).
+
+### qt_categories
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| code | varchar(20) UNIQUE NOT NULL | |
+| name | varchar(100) NOT NULL | |
+| name_ru | varchar(100) | |
+| display_order | bigint DEFAULT 0 | |
+| is_required | tinyint(1) DEFAULT 0 | |
+
+### qt_client_schema_state
+PK: (username, hostname)
+| Column | Type | Notes |
+|--------|------|-------|
+| username | varchar(100) | |
+| hostname | varchar(255) DEFAULT '' | |
+| last_applied_migration_id | varchar(128) | |
+| app_version | varchar(64) | |
+| last_sync_at | datetime | |
+| last_sync_status | varchar(32) | |
+| pending_changes_count | int DEFAULT 0 | |
+| pending_errors_count | int DEFAULT 0 | |
+| configurations_count | int DEFAULT 0 | |
+| projects_count | int DEFAULT 0 | |
+| estimate_pricelist_version | varchar(128) | |
+| warehouse_pricelist_version | varchar(128) | |
+| competitor_pricelist_version | varchar(128) | |
+| last_sync_error_code | varchar(128) | |
+| last_sync_error_text | text | |
+| last_checked_at | datetime NOT NULL | |
+| updated_at | datetime NOT NULL | |
+
+### qt_component_usage_stats
+PK: lot_name
+| Column | Type | Notes |
+|--------|------|-------|
+| lot_name | varchar(255) | |
+| quotes_total | bigint DEFAULT 0 | |
+| quotes_last30d | bigint DEFAULT 0 | |
+| quotes_last7d | bigint DEFAULT 0 | |
+| total_quantity | bigint DEFAULT 0 | |
+| total_revenue | decimal(14,2) DEFAULT 0 | |
+| trend_direction | enum('up','stable','down') DEFAULT 'stable' | |
+| trend_percent | decimal(5,2) DEFAULT 0 | |
+| last_used_at | datetime(3) | |
+
+### qt_competitors
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| name | varchar(255) NOT NULL | |
+| code | varchar(100) UNIQUE NOT NULL | |
+| delivery_basis | varchar(50) DEFAULT 'DDP' | |
+| currency | varchar(10) DEFAULT 'USD' | |
+| column_mapping | longtext JSON | |
+| is_active | tinyint(1) DEFAULT 1 | |
+| created_at | timestamp | |
+| updated_at | timestamp ON UPDATE | |
+| price_uplift | decimal(8,4) DEFAULT 1.3 | effective_price = price / price_uplift |
+
+### qt_configurations
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| uuid | varchar(36) UNIQUE NOT NULL | |
+| user_id | bigint UNSIGNED | |
+| owner_username | varchar(100) NOT NULL | |
+| app_version | varchar(64) | |
+| project_uuid | char(36) | FK → qt_projects.uuid ON DELETE SET NULL |
+| name | varchar(200) NOT NULL | |
+| items | longtext JSON NOT NULL | component list |
+| total_price | decimal(12,2) | |
+| notes | text | |
+| is_template | tinyint(1) DEFAULT 0 | |
+| created_at | datetime(3) | |
+| custom_price | decimal(12,2) | |
+| server_count | bigint DEFAULT 1 | |
+| server_model | varchar(100) | |
+| support_code | varchar(20) | |
+| article | varchar(80) | |
+| pricelist_id | bigint UNSIGNED | FK → qt_pricelists.id |
+| warehouse_pricelist_id | bigint UNSIGNED | FK → qt_pricelists.id |
+| competitor_pricelist_id | bigint UNSIGNED | FK → qt_pricelists.id |
+| disable_price_refresh | tinyint(1) DEFAULT 0 | |
+| only_in_stock | tinyint(1) DEFAULT 0 | |
+| line_no | int | position within project |
+| price_updated_at | timestamp | |
+| vendor_spec | longtext JSON | |
+
+### qt_lot_metadata
+PK: lot_name
+| Column | Type | Notes |
+|--------|------|-------|
+| lot_name | varchar(255) | |
+| category_id | bigint UNSIGNED | FK → qt_categories.id |
+| vendor | varchar(50) | |
+| model | varchar(100) | |
+| specs | longtext JSON | |
+| current_price | decimal(12,2) | cached computed price |
+| price_method | enum('manual','median','average','weighted_median') DEFAULT 'median' | |
+| price_period_days | bigint DEFAULT 90 | |
+| price_updated_at | datetime(3) | |
+| request_count | bigint DEFAULT 0 | |
+| last_request_date | date | |
+| popularity_score | decimal(10,4) DEFAULT 0 | |
+| price_coefficient | decimal(5,2) DEFAULT 0 | markup % |
+| manual_price | decimal(12,2) | |
+| meta_prices | varchar(1000) | raw price samples JSON |
+| meta_method | varchar(20) | method used for last compute |
+| meta_period_days | bigint DEFAULT 90 | |
+| is_hidden | tinyint(1) DEFAULT 0 | |
+
+### qt_partnumber_books
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| version | varchar(30) UNIQUE NOT NULL | |
+| created_at | timestamp | |
+| created_by | varchar(100) | |
+| is_active | tinyint(1) DEFAULT 0 | only one active at a time |
+| partnumbers_json | longtext DEFAULT '[]' | flat list of partnumbers |
+
+### qt_partnumber_book_items
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| partnumber | varchar(255) UNIQUE NOT NULL | |
+| lots_json | longtext NOT NULL | JSON array of lot_names |
+| description | varchar(10000) | |
+
+### qt_pricelists
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| source | varchar(20) DEFAULT 'estimate' | 'estimate' / 'warehouse' / 'competitor' |
+| version | varchar(20) NOT NULL | UNIQUE with source |
+| created_at | datetime(3) | |
+| created_by | varchar(100) | |
+| is_active | tinyint(1) DEFAULT 1 | |
+| usage_count | bigint DEFAULT 0 | |
+| expires_at | datetime(3) | |
+| notification | varchar(500) | shown to clients on sync |
+
+### qt_pricelist_items
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| pricelist_id | bigint UNSIGNED NOT NULL | FK → qt_pricelists.id |
+| lot_name | varchar(255) NOT NULL | INDEX with pricelist_id |
+| lot_category | varchar(50) | |
+| price | decimal(12,2) NOT NULL | |
+| price_method | varchar(20) | |
+| price_period_days | bigint DEFAULT 90 | |
+| price_coefficient | decimal(5,2) DEFAULT 0 | |
+| manual_price | decimal(12,2) | |
+| meta_prices | varchar(1000) | |
+
+### qt_pricelist_sync_status
+PK: username
+| Column | Type | Notes |
+|--------|------|-------|
+| username | varchar(100) | |
+| last_sync_at | datetime NOT NULL | |
+| updated_at | datetime NOT NULL | |
+| app_version | varchar(64) | |
+
+### qt_pricing_alerts
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| lot_name | varchar(255) NOT NULL | |
+| alert_type | enum('high_demand_stale_price','price_spike','price_drop','no_recent_quotes','trending_no_price') | |
+| severity | enum('low','medium','high','critical') DEFAULT 'medium' | |
+| message | text NOT NULL | |
+| details | longtext JSON | |
+| status | enum('new','acknowledged','resolved','ignored') DEFAULT 'new' | |
+| created_at | datetime(3) | |
+
+### qt_projects
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| uuid | char(36) UNIQUE NOT NULL | |
+| owner_username | varchar(100) NOT NULL | |
+| code | varchar(100) NOT NULL | UNIQUE with variant |
+| variant | varchar(100) DEFAULT '' | UNIQUE with code |
+| name | varchar(200) | |
+| tracker_url | varchar(500) | |
+| is_active | tinyint(1) DEFAULT 1 | |
+| is_system | tinyint(1) DEFAULT 0 | |
+| created_at | timestamp | |
+| updated_at | timestamp ON UPDATE | |
+
+### qt_schema_migrations
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| filename | varchar(255) UNIQUE NOT NULL | |
+| applied_at | datetime(3) | |
+
+### qt_scheduler_runs
+PK: job_name
+| Column | Type | Notes |
+|--------|------|-------|
+| job_name | varchar(100) | |
+| last_started_at | datetime | |
+| last_finished_at | datetime | |
+| last_status | varchar(20) DEFAULT 'idle' | |
+| last_error | text | |
+| updated_at | timestamp ON UPDATE | |
+
+### qt_vendor_partnumber_seen
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| source_type | varchar(32) NOT NULL | |
+| vendor | varchar(255) DEFAULT '' | |
+| partnumber | varchar(255) UNIQUE NOT NULL | |
+| description | varchar(10000) | |
+| last_seen_at | datetime(3) NOT NULL | |
+| is_ignored | tinyint(1) DEFAULT 0 | |
+| is_pattern | tinyint(1) DEFAULT 0 | |
+| ignored_at | datetime(3) | |
+| ignored_by | varchar(100) | |
+| created_at | datetime(3) | |
+| updated_at | datetime(3) | |
+
+### stock_ignore_rules
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| target | varchar(20) NOT NULL | UNIQUE with match_type+pattern |
+| match_type | varchar(20) NOT NULL | |
+| pattern | varchar(500) NOT NULL | |
+| created_at | timestamp | |
+
+### stock_log
+| Column | Type | Notes |
+|--------|------|-------|
+| stock_log_id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| partnumber | varchar(255) NOT NULL | INDEX with date |
+| supplier | varchar(255) | |
+| date | date NOT NULL | |
+| price | decimal(12,2) NOT NULL | |
+| quality | varchar(255) | |
+| comments | text | |
+| vendor | varchar(255) | INDEX |
+| qty | decimal(14,3) | |
+
+### partnumber_log_competitors
+| Column | Type | Notes |
+|--------|------|-------|
+| id | bigint UNSIGNED PK AUTO_INCREMENT | |
+| competitor_id | bigint UNSIGNED NOT NULL | FK → qt_competitors.id |
+| partnumber | varchar(255) NOT NULL | |
+| description | varchar(500) | |
+| vendor | varchar(255) | |
+| price | decimal(12,2) NOT NULL | |
+| price_loccur | decimal(12,2) | local currency price |
+| currency | varchar(10) | |
+| qty | decimal(12,4) DEFAULT 1 | |
+| date | date NOT NULL | |
+| created_at | timestamp | |
+
+### Legacy tables (lot / lot_log / machine / machine_log / supplier)
+
+Retained for historical data only. Not queried by QuoteForge.
+
+**lot**: lot_name (PK, char 255), lot_category, lot_description
+**lot_log**: lot_log_id AUTO_INCREMENT, lot (FK→lot), supplier (FK→supplier), date, price double, quality, comments
+**supplier**: supplier_name (PK, char 255), supplier_comment
+**machine**: machine_name (PK, char 255), machine_description
+**machine_log**: machine_log_id AUTO_INCREMENT, date, supplier (FK→supplier), country, opty, type, machine (FK→machine), customer_requirement, variant, price_gpl, price_estimate, qty, quality, carepack, lead_time_weeks, prepayment_percent, price_got, Comment
+
+## MariaDB User Permissions
+
+The application user needs read-only access to reference tables and read/write access to runtime tables.
+
+```sql
+-- Read-only: reference and pricing data
+GRANT SELECT ON RFQ_LOG.qt_categories            TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_lot_metadata          TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_pricelists            TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_pricelist_items       TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.stock_log                TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.stock_ignore_rules       TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_partnumber_books      TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_partnumber_book_items TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.lot                      TO 'qfs_user'@'%';
+
+-- Read/write: runtime sync and user data
+GRANT SELECT, INSERT, UPDATE, DELETE ON RFQ_LOG.qt_projects              TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE, DELETE ON RFQ_LOG.qt_configurations        TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE         ON RFQ_LOG.qt_client_schema_state   TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE         ON RFQ_LOG.qt_pricelist_sync_status TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE         ON RFQ_LOG.qt_vendor_partnumber_seen TO 'qfs_user'@'%';
+
+FLUSH PRIVILEGES;
+```
+
+Rules:
+- `qt_client_schema_state` requires INSERT + UPDATE for sync status tracking (uses `ON DUPLICATE KEY UPDATE`);
+- `qt_vendor_partnumber_seen` requires INSERT + UPDATE (vendor PN discovery during sync);
+- no DELETE is needed on sync/tracking tables — rows are never removed by the client;
+- `lot` SELECT is required for the connection validation probe in `/setup`;
+- the setup page shows `can_write: true` only when `qt_client_schema_state` INSERT succeeds.
 
 ## Migrations
 

cmd/qfs/main.go

@@ -1126,7 +1126,12 @@ func setupRouter(cfg *config.Config, local *localdb.LocalDB, connMgr *db.Connect
 
 			configs.POST("/:uuid/refresh-prices", func(c *gin.Context) {
 				uuid := c.Param("uuid")
-				config, err := configService.RefreshPricesNoAuth(uuid)
+				var req struct {
+					PricelistID *uint `json:"pricelist_id"`
+				}
+				// Ignore bind error — pricelist_id is optional
+				_ = c.ShouldBindJSON(&req)
+				config, err := configService.RefreshPricesNoAuth(uuid, req.PricelistID)
 				if err != nil {
 					respondError(c, http.StatusInternalServerError, "internal server error", err)
 					return
@@ -1539,7 +1544,8 @@ func setupRouter(cfg *config.Config, local *localdb.LocalDB, connMgr *db.Connect
 				project, err := projectService.Update(c.Param("uuid"), dbUsername, &req)
 				if err != nil {
 					switch {
-					case errors.Is(err, services.ErrReservedMainVariant):
+					case errors.Is(err, services.ErrReservedMainVariant),
+						errors.Is(err, services.ErrCannotRenameMainVariant):
 						respondError(c, http.StatusBadRequest, "invalid request", err)
 					case errors.Is(err, services.ErrProjectCodeExists):
 						respondError(c, http.StatusConflict, "conflict detected", err)

internal/handlers/web.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	qfassets "git.mchus.pro/mchus/quoteforge"
+	"git.mchus.pro/mchus/quoteforge/internal/appmeta"
 	"git.mchus.pro/mchus/quoteforge/internal/localdb"
 	"git.mchus.pro/mchus/quoteforge/internal/models"
 	"github.com/gin-gonic/gin"
@@ -112,6 +113,7 @@ func NewWebHandler(_ string, localDB *localdb.LocalDB) (*WebHandler, error) {
 }
 
 func (h *WebHandler) render(c *gin.Context, name string, data gin.H) {
+	data["AppVersion"] = appmeta.Version()
 	c.Header("Content-Type", "text/html; charset=utf-8")
 	tmpl, ok := h.templates[name]
 	if !ok {

internal/localdb/localdb.go

@@ -116,6 +116,14 @@ func New(dbPath string) (*LocalDB, error) {
 		return nil, fmt.Errorf("opening sqlite database: %w", err)
 	}
 
+	// Enable WAL mode so background sync writes never block UI reads.
+	if err := db.Exec("PRAGMA journal_mode=WAL").Error; err != nil {
+		slog.Warn("failed to enable WAL mode", "error", err)
+	}
+	if err := db.Exec("PRAGMA synchronous=NORMAL").Error; err != nil {
+		slog.Warn("failed to set synchronous=NORMAL", "error", err)
+	}
+
 	if err := ensureLocalProjectsTable(db); err != nil {
 		return nil, fmt.Errorf("ensure local_projects table: %w", err)
 	}
@@ -1152,6 +1160,29 @@ func (l *LocalDB) CountLocalPricelists() int64 {
 	return count
 }
 
+// CountAllPricelistItems returns total rows across all local_pricelist_items.
+func (l *LocalDB) CountAllPricelistItems() int64 {
+	var count int64
+	l.db.Model(&LocalPricelistItem{}).Count(&count)
+	return count
+}
+
+// CountComponents returns the number of rows in local_components.
+func (l *LocalDB) CountComponents() int64 {
+	var count int64
+	l.db.Model(&LocalComponent{}).Count(&count)
+	return count
+}
+
+// DBFileSizeBytes returns the size of the SQLite database file in bytes.
+func (l *LocalDB) DBFileSizeBytes() int64 {
+	info, err := os.Stat(l.path)
+	if err != nil {
+		return 0
+	}
+	return info.Size()
+}
+
 // GetLatestLocalPricelist returns the most recently synced pricelist
 func (l *LocalDB) GetLatestLocalPricelist() (*LocalPricelist, error) {
 	var pricelist LocalPricelist
@@ -1319,6 +1350,32 @@ func (l *LocalDB) GetLocalPriceForLot(pricelistID uint, lotName string) (float64
 	return item.Price, nil
 }
 
+// GetLocalPricesForLots returns prices for multiple lots from a local pricelist in a single query.
+// Uses the composite index (pricelist_id, lot_name). Missing lots are omitted from the result.
+func (l *LocalDB) GetLocalPricesForLots(pricelistID uint, lotNames []string) (map[string]float64, error) {
+	result := make(map[string]float64, len(lotNames))
+	if len(lotNames) == 0 {
+		return result, nil
+	}
+	type row struct {
+		LotName string  `gorm:"column:lot_name"`
+		Price   float64 `gorm:"column:price"`
+	}
+	var rows []row
+	if err := l.db.Model(&LocalPricelistItem{}).
+		Select("lot_name, price").
+		Where("pricelist_id = ? AND lot_name IN ?", pricelistID, lotNames).
+		Find(&rows).Error; err != nil {
+		return nil, err
+	}
+	for _, r := range rows {
+		if r.Price > 0 {
+			result[r.LotName] = r.Price
+		}
+	}
+	return result, nil
+}
+
 // GetLocalLotCategoriesByServerPricelistID returns lot_category for each lot_name from a local pricelist resolved by server ID.
 // Missing lots are not included in the map; caller is responsible for strict validation.
 func (l *LocalDB) GetLocalLotCategoriesByServerPricelistID(serverPricelistID uint, lotNames []string) (map[string]string, error) {

internal/services/local_configuration.go

@@ -49,11 +49,13 @@ func NewLocalConfigurationService(
 
 // Create creates a new configuration in local SQLite and queues it for sync
 func (s *LocalConfigurationService) Create(ownerUsername string, req *CreateConfigRequest) (*models.Configuration, error) {
-	// If online, check for new pricelists first
+	// If online, trigger pricelist sync in the background — do not block config creation
 	if s.isOnline() {
-		if err := s.syncService.SyncPricelistsIfNeeded(); err != nil {
-			// Log but don't fail - we can still use local pricelists
-		}
+		go func() {
+			if err := s.syncService.SyncPricelistsIfNeeded(); err != nil {
+				// Log but don't fail - we can still use local pricelists
+			}
+		}()
 	}
 
 	projectUUID, err := s.resolveProjectUUID(ownerUsername, req.ProjectUUID)
@@ -399,17 +401,29 @@ func (s *LocalConfigurationService) RefreshPrices(uuid string, ownerUsername str
 		return nil, ErrConfigForbidden
 	}
 
-	// Refresh local pricelists when online and use latest active/local pricelist for recalculation.
+	// Refresh local pricelists when online.
 	if s.isOnline() {
 		_ = s.syncService.SyncPricelistsIfNeeded()
 	}
-	latestPricelist, latestErr := s.localDB.GetLatestLocalPricelist()
+
+	// Use the pricelist stored in the config; fall back to latest if unavailable.
+	var pricelist *localdb.LocalPricelist
+	if localCfg.PricelistID != nil && *localCfg.PricelistID > 0 {
+		if pl, err := s.localDB.GetLocalPricelistByServerID(*localCfg.PricelistID); err == nil {
+			pricelist = pl
+		}
+	}
+	if pricelist == nil {
+		if pl, err := s.localDB.GetLatestLocalPricelist(); err == nil {
+			pricelist = pl
+		}
+	}
 
 	// Update prices for all items from pricelist
 	updatedItems := make(localdb.LocalConfigItems, len(localCfg.Items))
 	for i, item := range localCfg.Items {
-		if latestErr == nil && latestPricelist != nil {
-			price, err := s.localDB.GetLocalPriceForLot(latestPricelist.ID, item.LotName)
+		if pricelist != nil {
+			price, err := s.localDB.GetLocalPriceForLot(pricelist.ID, item.LotName)
 			if err == nil && price > 0 {
 				updatedItems[i] = localdb.LocalConfigItem{
 					LotName:   item.LotName,
@@ -434,8 +448,8 @@ func (s *LocalConfigurationService) RefreshPrices(uuid string, ownerUsername str
 	}
 
 	localCfg.TotalPrice = &total
-	if latestErr == nil && latestPricelist != nil {
-		localCfg.PricelistID = &latestPricelist.ServerID
+	if pricelist != nil {
+		localCfg.PricelistID = &pricelist.ServerID
 	}
 
 	// Set price update timestamp and mark for sync
@@ -762,8 +776,10 @@ func (s *LocalConfigurationService) ListTemplates(page, perPage int) ([]models.C
 	return templates[start:end], total, nil
 }
 
-// RefreshPricesNoAuth updates all component prices in the configuration without ownership check
-func (s *LocalConfigurationService) RefreshPricesNoAuth(uuid string) (*models.Configuration, error) {
+// RefreshPricesNoAuth updates all component prices in the configuration without ownership check.
+// pricelistServerID optionally specifies which pricelist to use; if nil, the config's stored
+// pricelist is used; if that is also absent, the latest local pricelist is used as a fallback.
+func (s *LocalConfigurationService) RefreshPricesNoAuth(uuid string, pricelistServerID *uint) (*models.Configuration, error) {
 	// Get configuration from local SQLite
 	localCfg, err := s.localDB.GetConfigurationByUUID(uuid)
 	if err != nil {
@@ -773,13 +789,36 @@ func (s *LocalConfigurationService) RefreshPricesNoAuth(uuid string) (*models.Co
 	if s.isOnline() {
 		_ = s.syncService.SyncPricelistsIfNeeded()
 	}
-	latestPricelist, latestErr := s.localDB.GetLatestLocalPricelist()
+
+	// Resolve which pricelist to use:
+	// 1. Explicitly requested pricelist (from UI selection)
+	// 2. Pricelist stored in the configuration
+	// 3. Latest local pricelist as last-resort fallback
+	var targetServerID *uint
+	if pricelistServerID != nil && *pricelistServerID > 0 {
+		targetServerID = pricelistServerID
+	} else if localCfg.PricelistID != nil && *localCfg.PricelistID > 0 {
+		targetServerID = localCfg.PricelistID
+	}
+
+	var pricelist *localdb.LocalPricelist
+	if targetServerID != nil {
+		if pl, err := s.localDB.GetLocalPricelistByServerID(*targetServerID); err == nil {
+			pricelist = pl
+		}
+	}
+	if pricelist == nil {
+		// Fallback: use latest local pricelist
+		if pl, err := s.localDB.GetLatestLocalPricelist(); err == nil {
+			pricelist = pl
+		}
+	}
 
 	// Update prices for all items from pricelist
 	updatedItems := make(localdb.LocalConfigItems, len(localCfg.Items))
 	for i, item := range localCfg.Items {
-		if latestErr == nil && latestPricelist != nil {
-			price, err := s.localDB.GetLocalPriceForLot(latestPricelist.ID, item.LotName)
+		if pricelist != nil {
+			price, err := s.localDB.GetLocalPriceForLot(pricelist.ID, item.LotName)
 			if err == nil && price > 0 {
 				updatedItems[i] = localdb.LocalConfigItem{
 					LotName:   item.LotName,
@@ -804,8 +843,8 @@ func (s *LocalConfigurationService) RefreshPricesNoAuth(uuid string) (*models.Co
 	}
 
 	localCfg.TotalPrice = &total
-	if latestErr == nil && latestPricelist != nil {
-		localCfg.PricelistID = &latestPricelist.ServerID
+	if pricelist != nil {
+		localCfg.PricelistID = &pricelist.ServerID
 	}
 
 	// Set price update timestamp and mark for sync

internal/services/project.go

@@ -21,6 +21,7 @@ var (
 	ErrProjectCodeExists       = errors.New("project code and variant already exist")
 	ErrCannotDeleteMainVariant = errors.New("cannot delete main variant")
 	ErrReservedMainVariant     = errors.New("variant name 'main' is reserved")
+	ErrCannotRenameMainVariant = errors.New("cannot rename main variant")
 )
 
 type ProjectService struct {
@@ -108,7 +109,12 @@ func (s *ProjectService) Update(projectUUID, ownerUsername string, req *UpdatePr
 		localProject.Code = code
 	}
 	if req.Variant != nil {
-		localProject.Variant = strings.TrimSpace(*req.Variant)
+		newVariant := strings.TrimSpace(*req.Variant)
+		// Block renaming of the main variant (empty Variant) — there must always be a main.
+		if strings.TrimSpace(localProject.Variant) == "" && newVariant != "" {
+			return nil, ErrCannotRenameMainVariant
+		}
+		localProject.Variant = newVariant
 		if err := validateProjectVariantName(localProject.Variant); err != nil {
 			return nil, err
 		}

internal/services/quote.go

@@ -388,13 +388,14 @@ func (s *QuoteService) lookupPricesByPricelistID(pricelistID uint, lotNames []st
 		}
 	}
 
-	// Fallback path (usually offline): local per-lot lookup.
+	// Fallback path (usually offline): batch local lookup (single query via index).
 	if s.localDB != nil {
-		for _, lotName := range missing {
-			price, found := s.lookupPriceByPricelistID(pricelistID, lotName)
-			if found && price > 0 {
-				result[lotName] = price
-				loaded[lotName] = price
+		if localPL, err := s.localDB.GetLocalPricelistByServerID(pricelistID); err == nil {
+			if batchPrices, err := s.localDB.GetLocalPricesForLots(localPL.ID, missing); err == nil {
+				for lotName, price := range batchPrices {
+					result[lotName] = price
+					loaded[lotName] = price
+				}
 			}
 		}
 		s.updateCache(pricelistID, missing, loaded)

internal/services/sync/readiness.go

@@ -168,6 +168,10 @@ func ensureClientSchemaStateTable(db *gorm.DB) error {
 			"ALTER TABLE qt_client_schema_state ADD COLUMN IF NOT EXISTS competitor_pricelist_version VARCHAR(128) NULL AFTER warehouse_pricelist_version",
 			"ALTER TABLE qt_client_schema_state ADD COLUMN IF NOT EXISTS last_sync_error_code VARCHAR(128) NULL AFTER competitor_pricelist_version",
 			"ALTER TABLE qt_client_schema_state ADD COLUMN IF NOT EXISTS last_sync_error_text TEXT NULL AFTER last_sync_error_code",
+			"ALTER TABLE qt_client_schema_state ADD COLUMN IF NOT EXISTS local_pricelist_count INT NOT NULL DEFAULT 0 AFTER last_sync_error_text",
+			"ALTER TABLE qt_client_schema_state ADD COLUMN IF NOT EXISTS pricelist_items_count INT NOT NULL DEFAULT 0 AFTER local_pricelist_count",
+			"ALTER TABLE qt_client_schema_state ADD COLUMN IF NOT EXISTS components_count INT NOT NULL DEFAULT 0 AFTER pricelist_items_count",
+			"ALTER TABLE qt_client_schema_state ADD COLUMN IF NOT EXISTS db_size_bytes BIGINT NOT NULL DEFAULT 0 AFTER components_count",
 		} {
 			if err := db.Exec(stmt).Error; err != nil {
 				return fmt.Errorf("expand qt_client_schema_state: %w", err)
@@ -215,6 +219,10 @@ func (s *Service) reportClientSchemaState(mariaDB *gorm.DB, checkedAt time.Time)
 	warehouseVersion := latestPricelistVersion(s.localDB, "warehouse")
 	competitorVersion := latestPricelistVersion(s.localDB, "competitor")
 	lastSyncErrorCode, lastSyncErrorText := latestSyncErrorState(s.localDB)
+	localPricelistCount := s.localDB.CountLocalPricelists()
+	pricelistItemsCount := s.localDB.CountAllPricelistItems()
+	componentsCount := s.localDB.CountComponents()
+	dbSizeBytes := s.localDB.DBFileSizeBytes()
 	return mariaDB.Exec(`
 		INSERT INTO qt_client_schema_state (
 			username, hostname, app_version,
@@ -222,9 +230,10 @@ func (s *Service) reportClientSchemaState(mariaDB *gorm.DB, checkedAt time.Time)
 			configurations_count, projects_count,
 			estimate_pricelist_version, warehouse_pricelist_version, competitor_pricelist_version,
 			last_sync_error_code, last_sync_error_text,
+			local_pricelist_count, pricelist_items_count, components_count, db_size_bytes,
 			last_checked_at, updated_at
 		)
-		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
 		ON DUPLICATE KEY UPDATE
 			app_version = VALUES(app_version),
 			last_sync_at = VALUES(last_sync_at),
@@ -238,6 +247,10 @@ func (s *Service) reportClientSchemaState(mariaDB *gorm.DB, checkedAt time.Time)
 			competitor_pricelist_version = VALUES(competitor_pricelist_version),
 			last_sync_error_code = VALUES(last_sync_error_code),
 			last_sync_error_text = VALUES(last_sync_error_text),
+			local_pricelist_count = VALUES(local_pricelist_count),
+			pricelist_items_count = VALUES(pricelist_items_count),
+			components_count = VALUES(components_count),
+			db_size_bytes = VALUES(db_size_bytes),
 			last_checked_at = VALUES(last_checked_at),
 			updated_at = VALUES(updated_at)
 	`, username, hostname, appmeta.Version(),
@@ -245,6 +258,7 @@ func (s *Service) reportClientSchemaState(mariaDB *gorm.DB, checkedAt time.Time)
 		configurationsCount, projectsCount,
 		estimateVersion, warehouseVersion, competitorVersion,
 		lastSyncErrorCode, lastSyncErrorText,
+		localPricelistCount, pricelistItemsCount, componentsCount, dbSizeBytes,
 		checkedAt, checkedAt).Error
 }
 

internal/services/sync/service.go

@@ -7,6 +7,7 @@ import (
 	"log/slog"
 	"sort"
 	"strings"
+	"sync"
 	"time"
 
 	"git.mchus.pro/mchus/quoteforge/internal/appmeta"
@@ -22,9 +23,10 @@ var ErrOffline = errors.New("database is offline")
 
 // Service handles synchronization between MariaDB and local SQLite
 type Service struct {
-	connMgr  *db.ConnectionManager
-	localDB  *localdb.LocalDB
-	directDB *gorm.DB
+	connMgr     *db.ConnectionManager
+	localDB     *localdb.LocalDB
+	directDB    *gorm.DB
+	pricelistMu sync.Mutex // prevents concurrent pricelist syncs
 }
 
 // NewService creates a new sync service
@@ -939,9 +941,15 @@ func (s *Service) GetPricelistForOffline(serverPricelistID uint) (*localdb.Local
 	return localPL, nil
 }
 
-// SyncPricelistsIfNeeded checks for new pricelists and syncs if needed
-// This should be called before creating a new configuration when online
+// SyncPricelistsIfNeeded checks for new pricelists and syncs if needed.
+// If a sync is already in progress, returns immediately without blocking.
 func (s *Service) SyncPricelistsIfNeeded() error {
+	if !s.pricelistMu.TryLock() {
+		slog.Debug("pricelist sync already in progress, skipping")
+		return nil
+	}
+	defer s.pricelistMu.Unlock()
+
 	needSync, err := s.NeedSync()
 	if err != nil {
 		slog.Warn("failed to check if sync needed", "error", err)

web/templates/base.html

@@ -44,6 +44,10 @@
         {{template "content" .}}
     </main>
 
+    <footer class="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-3 text-right">
+        <span class="text-xs text-gray-400">v{{.AppVersion}}</span>
+    </footer>
+
     <div id="toast" class="fixed bottom-4 right-4 z-50"></div>
 
     <!-- Sync Info Modal -->

web/templates/config_revisions.html

@@ -1,4 +1,4 @@
-{{define "title"}}Ревизии - QuoteForge{{end}}
+{{define "title"}}Ревизии - OFS{{end}}
 
 {{define "content"}}
 <div class="space-y-4">

web/templates/configs.html

@@ -1,4 +1,4 @@
-{{define "title"}}Мои конфигурации - QuoteForge{{end}}
+{{define "title"}}Мои конфигурации - OFS{{end}}
 
 {{define "content"}}
 <div class="space-y-4">

web/templates/index.html

@@ -1,4 +1,4 @@
-{{define "title"}}QuoteForge - Конфигуратор{{end}}
+{{define "title"}}OFS - Конфигуратор{{end}}
 
 {{define "content"}}
 <div class="space-y-4">
@@ -477,6 +477,7 @@ function updateConfigBreadcrumbs() {
     configEl.textContent = truncateBreadcrumbSpecName(fullConfigName);
     configEl.title = fullConfigName;
     versionEl.textContent = 'main';
+    document.title = code + ' / ' + variant + ' / ' + fullConfigName + ' — OFS';
     const configNameLinkEl = document.getElementById('breadcrumb-config-name-link');
     if (configNameLinkEl && configUUID) {
         configNameLinkEl.href = '/configs/' + configUUID + '/revisions';
@@ -925,14 +926,9 @@ async function loadActivePricelists(force = false) {
                 const resp = await fetch(`/api/pricelists?active_only=true&source=${source}&per_page=200`);
                 const data = await resp.json();
                 activePricelistsBySource[source] = data.pricelists || [];
-                const existing = selectedPricelistIds[source];
-                if (existing && activePricelistsBySource[source].some(pl => Number(pl.id) === Number(existing))) {
-                    return;
-                }
-                selectedPricelistIds[source] = null;
+                // Do not reset the stored pricelist — it may be inactive but must be preserved
             } catch (e) {
                 activePricelistsBySource[source] = [];
-                selectedPricelistIds[source] = null;
             }
         }));
         activePricelistsLoadedAt = Date.now();
@@ -954,11 +950,25 @@ function renderPricelistSelectOptions(selectId, source) {
         select.value = '';
         return;
     }
-    select.innerHTML = `<option value="">Авто (последний активный)</option>` + pricelists.map(pl => {
+    select.innerHTML = pricelists.map(pl => {
         return `<option value="${pl.id}">${escapeHtml(pl.version)}</option>`;
     }).join('');
     const current = selectedPricelistIds[source];
-    select.value = current ? String(current) : '';
+    if (current) {
+        select.value = String(current);
+        // Stored pricelist may be inactive — add it as a virtual option if not found
+        if (!select.value) {
+            const opt = document.createElement('option');
+            opt.value = String(current);
+            opt.textContent = `ID ${current} (неактивный)`;
+            select.prepend(opt);
+            select.value = String(current);
+        }
+    } else if (pricelists.length > 0) {
+        // New config: pre-select the first (latest) pricelist
+        selectedPricelistIds[source] = Number(pricelists[0].id);
+        select.value = String(pricelists[0].id);
+    }
 }
 
 function syncPriceSettingsControls() {
@@ -984,9 +994,9 @@ function getPricelistVersionById(source, id) {
 function renderPricelistSettingsSummary() {
     const summary = document.getElementById('pricelist-settings-summary');
     if (!summary) return;
-    const estimate = selectedPricelistIds.estimate ? getPricelistVersionById('estimate', selectedPricelistIds.estimate) || `ID ${selectedPricelistIds.estimate}` : 'авто';
-    const warehouse = selectedPricelistIds.warehouse ? getPricelistVersionById('warehouse', selectedPricelistIds.warehouse) || `ID ${selectedPricelistIds.warehouse}` : 'авто';
-    const competitor = selectedPricelistIds.competitor ? getPricelistVersionById('competitor', selectedPricelistIds.competitor) || `ID ${selectedPricelistIds.competitor}` : 'авто';
+    const estimate = selectedPricelistIds.estimate ? getPricelistVersionById('estimate', selectedPricelistIds.estimate) || `ID ${selectedPricelistIds.estimate}` : '—';
+    const warehouse = selectedPricelistIds.warehouse ? getPricelistVersionById('warehouse', selectedPricelistIds.warehouse) || `ID ${selectedPricelistIds.warehouse}` : '—';
+    const competitor = selectedPricelistIds.competitor ? getPricelistVersionById('competitor', selectedPricelistIds.competitor) || `ID ${selectedPricelistIds.competitor}` : '—';
     const refreshState = disablePriceRefresh ? ' | Обновление цен: выкл' : '';
     const stockFilterState = onlyInStock ? ' | Только наличие: вкл' : '';
     summary.textContent = `Estimate: ${estimate}, Склад: ${warehouse}, Конкуренты: ${competitor}${refreshState}${stockFilterState}`;
@@ -1062,16 +1072,16 @@ function applyPriceSettings() {
     const inStockVal = Boolean(document.getElementById('settings-only-in-stock')?.checked);
 
     const prevWarehouseID = currentWarehousePricelistID();
-    selectedPricelistIds.estimate = Number.isFinite(estimateVal) && estimateVal > 0 ? estimateVal : null;
-    selectedPricelistIds.warehouse = Number.isFinite(warehouseVal) && warehouseVal > 0 ? warehouseVal : null;
-    selectedPricelistIds.competitor = Number.isFinite(competitorVal) && competitorVal > 0 ? competitorVal : null;
-    if (selectedPricelistIds.estimate) {
+    if (Number.isFinite(estimateVal) && estimateVal > 0) {
+        selectedPricelistIds.estimate = estimateVal;
         resolvedAutoPricelistIds.estimate = null;
     }
-    if (selectedPricelistIds.warehouse) {
+    if (Number.isFinite(warehouseVal) && warehouseVal > 0) {
+        selectedPricelistIds.warehouse = warehouseVal;
         resolvedAutoPricelistIds.warehouse = null;
     }
-    if (selectedPricelistIds.competitor) {
+    if (Number.isFinite(competitorVal) && competitorVal > 0) {
+        selectedPricelistIds.competitor = competitorVal;
         resolvedAutoPricelistIds.competitor = null;
     }
     disablePriceRefresh = disableVal;
@@ -2508,11 +2518,14 @@ async function refreshPrices() {
     }
 
     try {
+        const refreshPayload = {};
+        if (selectedPricelistIds.estimate) {
+            refreshPayload.pricelist_id = selectedPricelistIds.estimate;
+        }
         const resp = await fetch('/api/configs/' + configUUID + '/refresh-prices', {
             method: 'POST',
-            headers: {
-                'Content-Type': 'application/json'
-            }
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify(refreshPayload)
         });
 
         if (!resp.ok) {

web/templates/partnumber_books.html

@@ -1,4 +1,4 @@
-{{define "title"}}QuoteForge - Партномера{{end}}
+{{define "title"}}OFS - Партномера{{end}}
 
 {{define "content"}}
 <div class="space-y-4">

web/templates/pricelist_detail.html

@@ -1,4 +1,4 @@
-{{define "title"}}Прайслист - QuoteForge{{end}}
+{{define "title"}}Прайслист - OFS{{end}}
 
 {{define "content"}}
 <div class="space-y-6">

web/templates/pricelists.html

@@ -1,4 +1,4 @@
-{{define "title"}}Прайслисты - QuoteForge{{end}}
+{{define "title"}}Прайслисты - OFS{{end}}
 
 {{define "content"}}
 <div class="space-y-6">

web/templates/project_detail.html

@@ -1,4 +1,4 @@
-{{define "title"}}Проект - QuoteForge{{end}}
+{{define "title"}}Проект - OFS{{end}}
 
 {{define "content"}}
 <div class="space-y-4">
@@ -363,6 +363,7 @@ function renderVariantSelect() {
         if (item.uuid === projectUUID) {
             option.className += ' font-semibold text-gray-900';
             label.textContent = variantLabel;
+            document.title = (project && project.code ? project.code : '—') + ' / ' + variantLabel + ' — OFS';
         }
         option.textContent = variantLabel;
         option.onclick = function() {

web/templates/projects.html

@@ -1,4 +1,4 @@
-{{define "title"}}Мои проекты - QuoteForge{{end}}
+{{define "title"}}Мои проекты - OFS{{end}}
 
 {{define "content"}}
 <div class="space-y-4">

web/templates/setup.html

@@ -4,7 +4,7 @@
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>QuoteForge - Настройка подключения</title>
+    <title>OFS - Настройка подключения</title>
     <link rel="stylesheet" href="/static/app.css">
     <script src="/static/vendor/tailwindcss.browser.js"></script>
 </head>