refactor(knowledge): migrate deleted-item cleanup from polling scheduler to event-driven worker

Replaces the scheduler-polled KnowledgeDeletedCleanupWorker with an
event-driven KnowledgeDeletedCleanupEventWorker in tenant-api; cleanup
events are now enqueued transactionally at delete time instead of swept
periodically. Also fixes statement_timeout parameterization in
MonitoringRetentionWorker and propagates errors from cleanupDeletedKnowledgeItem.

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

server/cmd/scheduler/main.go

@@ -91,7 +91,6 @@ func main() {
 	monitoringResultRecoveryWorker := internalscheduler.NewMonitoringResultRecoveryWorker(app.MonitoringDB, monitoringCallbackService, app.Logger)
 	monitoringLeaseRecoveryWorker := internalscheduler.NewMonitoringLeaseRecoveryWorker(app.MonitoringDB, app.Logger)
 	monitoringReceivedInspectionWorker := internalscheduler.NewMonitoringReceivedInspectionWorker(app.MonitoringDB, app.Logger)
-	knowledgeDeletedCleanupWorker := internalscheduler.NewKnowledgeDeletedCleanupWorker(knowledgeSvc)
 	generationStateCheckWorker := generateworker.NewGenerationTaskStateCheckWorker(app.DB, app.Logger, app.Config().Generation).
 		WithConfigProvider(app.ConfigStore).
 		WithCache(app.Cache)
@@ -128,12 +127,6 @@ func main() {
 				return monitoringReceivedInspectionWorker.RunOnce(runCtx)
 			},
 		},
-		{
-			Key: "knowledge_deleted_cleanup",
-			Run: func(runCtx context.Context, _ internalscheduler.JobRunContext) (map[string]any, error) {
-				return knowledgeDeletedCleanupWorker.RunOnce(runCtx)
-			},
-		},
 		{
 			Key: "generation_state_check",
 			Run: func(runCtx context.Context, _ internalscheduler.JobRunContext) (map[string]any, error) {

server/cmd/tenant-api/main.go

@@ -42,6 +42,19 @@ func main() {
 	tenantapp.NewDesktopAccountHealthSinkWorker(app.DB, app.RabbitMQ, app.Logger).Start(workerCtx)
 	imageService := tenantapp.NewImageService(app.DB, app.ObjectStorage, app.RabbitMQ, app.Logger)
 	tenantapp.NewImageAssetWorker(imageService, app.RabbitMQ, app.Logger).Start(workerCtx)
+	knowledgeCleanupService := tenantapp.NewKnowledgeService(
+		app.DB,
+		app.RetrievalProvider,
+		app.VectorStore,
+		app.ObjectStorage,
+		app.LLM,
+		app.Logger,
+		app.Config().Retrieval,
+		app.Config().LLM,
+		0,
+		0,
+	).WithConfigProvider(app.ConfigStore)
+	tenantapp.NewKnowledgeDeletedCleanupEventWorker(knowledgeCleanupService, app.Logger).Start(workerCtx)
 
 	transport.RegisterRoutes(app)