Add offline RefreshPrices, fix sync bugs, implement auto-restart

- Implement RefreshPrices for local-first mode
  - Update prices from local_components.current_price cache
  - Graceful degradation when component not found
  - Add PriceUpdatedAt timestamp to LocalConfiguration model
  - Support both authenticated and no-auth price refresh

- Fix sync duplicate entry bug
  - pushConfigurationUpdate now ensures server_id exists before update
  - Fetch from LocalConfiguration.ServerID or search on server if missing
  - Update local config with server_id after finding

- Add application auto-restart after settings save
  - Implement restartProcess() using syscall.Exec
  - Setup handler signals restart via channel
  - Setup page polls /health endpoint and redirects when ready
  - Add "Back" button on setup page when settings exist

- Fix setup handler password handling
  - Use PasswordEncrypted field consistently
  - Support empty password by using saved value

- Improve sync status handling
  - Add fallback for is_offline check in SyncStatusPartial
  - Enhance background sync logging with prefixes

- Update CLAUDE.md documentation
  - Mark Phase 2.5 tasks as complete
  - Add UI Improvements section with future tasks
  - Update SQLite tables documentation

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

internal/localdb/converters.go

@@ -26,6 +26,7 @@ func ConfigurationToLocal(cfg *models.Configuration) *LocalConfiguration {
 		Notes:          cfg.Notes,
 		IsTemplate:     cfg.IsTemplate,
 		ServerCount:    cfg.ServerCount,
+		PriceUpdatedAt: cfg.PriceUpdatedAt,
 		CreatedAt:      cfg.CreatedAt,
 		UpdatedAt:      time.Now(),
 		SyncStatus:     "pending",
@@ -52,16 +53,17 @@ func LocalToConfiguration(local *LocalConfiguration) *models.Configuration {
 	}
 
 	cfg := &models.Configuration{
-		UUID:        local.UUID,
-		UserID:      local.OriginalUserID,
-		Name:        local.Name,
-		Items:       items,
-		TotalPrice:  local.TotalPrice,
-		CustomPrice: local.CustomPrice,
-		Notes:       local.Notes,
-		IsTemplate:  local.IsTemplate,
-		ServerCount: local.ServerCount,
-		CreatedAt:   local.CreatedAt,
+		UUID:           local.UUID,
+		UserID:         local.OriginalUserID,
+		Name:           local.Name,
+		Items:          items,
+		TotalPrice:     local.TotalPrice,
+		CustomPrice:    local.CustomPrice,
+		Notes:          local.Notes,
+		IsTemplate:     local.IsTemplate,
+		ServerCount:    local.ServerCount,
+		PriceUpdatedAt: local.PriceUpdatedAt,
+		CreatedAt:      local.CreatedAt,
 	}
 
 	if local.ServerID != nil {

internal/localdb/models.go

@@ -69,6 +69,7 @@ type LocalConfiguration struct {
 	Notes          string           `json:"notes"`
 	IsTemplate     bool             `gorm:"default:false" json:"is_template"`
 	ServerCount    int              `gorm:"default:1" json:"server_count"`
+	PriceUpdatedAt *time.Time       `gorm:"type:timestamp" json:"price_updated_at,omitempty"`
 	CreatedAt      time.Time        `json:"created_at"`
 	UpdatedAt      time.Time        `json:"updated_at"`
 	SyncedAt       *time.Time       `json:"synced_at"`