refactor: убрать qt_pricelist_sync_status, lot_log и лишние права БД

- Удалить все записи в qt_pricelist_sync_status (RecordSyncHeartbeat и
  ensureUserSyncStatusTable); ListUserSyncStatuses переведён на
  qt_client_schema_state
- Подавлять устаревший OFFLINE_UNVERIFIED_SCHEMA в UI когда соединение
  уже восстановлено
- Удалить все обращения к lot_log: repository/price.go, сортировка
  quote_count в component.go, UpdatePopularityScores в stats.go,
  модель LotLog

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

internal/handlers/sync.go

@@ -238,7 +238,6 @@ func (h *SyncHandler) SyncPricelists(c *gin.Context) {
 		Synced:   synced,
 		Duration: time.Since(startTime).String(),
 	})
-	h.syncService.RecordSyncHeartbeat()
 }
 
 // SyncPartnumberBooks syncs partnumber book snapshots from MariaDB to local SQLite.
@@ -266,7 +265,6 @@ func (h *SyncHandler) SyncPartnumberBooks(c *gin.Context) {
 		Synced:   pulled,
 		Duration: time.Since(startTime).String(),
 	})
-	h.syncService.RecordSyncHeartbeat()
 }
 
 // SyncAllResponse represents result of full sync
@@ -399,7 +397,6 @@ func (h *SyncHandler) SyncAll(c *gin.Context) {
 		ConfigurationsSkipped:  configsResult.Skipped,
 		Duration:               time.Since(startTime).String(),
 	})
-	h.syncService.RecordSyncHeartbeat()
 }
 
 // checkOnline checks if MariaDB is accessible
@@ -432,7 +429,6 @@ func (h *SyncHandler) PushPendingChanges(c *gin.Context) {
 		Synced:   pushed,
 		Duration: time.Since(startTime).String(),
 	})
-	h.syncService.RecordSyncHeartbeat()
 }
 
 // GetPendingCount returns the number of pending changes
@@ -621,9 +617,6 @@ func (h *SyncHandler) GetUsersStatus(c *gin.Context) {
 		return
 	}
 
-	// Keep current client heartbeat fresh so app version is available in the table.
-	h.syncService.RecordSyncHeartbeat()
-
 	users, err := h.syncService.ListUserSyncStatuses(threshold)
 	if err != nil {
 		RespondError(c, http.StatusInternalServerError, "internal server error", err)
@@ -712,6 +705,13 @@ func (h *SyncHandler) getReadinessLocal() *sync.SyncReadiness {
 		return nil
 	}
 
+	// OFFLINE_UNVERIFIED_SCHEMA is only valid while actually offline.
+	// Suppress it when the connection manager reports online so the stale
+	// blocked state from a previous disconnection doesn't linger in the UI.
+	if state.ReasonCode == "OFFLINE_UNVERIFIED_SCHEMA" && h.checkOnline() {
+		return nil
+	}
+
 	readiness := &sync.SyncReadiness{
 		Status:                state.Status,
 		Blocked:               state.Status == sync.ReadinessBlocked,