feat: Implement cancellation of stale generations in the service and repository, along with a new test.

aiws.py

@@ -120,6 +120,17 @@ assets_router.message.middleware(AuthMiddleware(repo=users_repo, admin_id=ADMIN_
 gen_router.message.middleware(AlbumMiddleware(latency=0.8))
 
 
+async def start_scheduler(service: GenerationService):
+    while True:
+        try:
+            logger.info("Running scheduler for stacked generation killing")
+            await service.cleanup_stale_generations()
+        except asyncio.CancelledError:
+             break
+        except Exception as e:
+            logger.error(f"Scheduler error: {e}")
+        await asyncio.sleep(300) # Check every 5 minutes
+
 # --- LIFESPAN (Запуск FastAPI + Bot) ---
 @asynccontextmanager
 async def lifespan(app: FastAPI):
@@ -151,17 +162,28 @@ async def lifespan(app: FastAPI):
     # )
     # print("🤖 Bot polling started")
 
+    # 3. ЗАПУСК ШЕДУЛЕРА
+    scheduler_task = asyncio.create_task(start_scheduler(generation_service))
+    print("⏰ Scheduler started")
+
     yield
 
     # --- SHUTDOWN ---
     print("🛑 Shutting down...")
-
-    # 3. Остановка бота
-    polling_task.cancel()
+    
+    # 4. Остановка шедулера
+    scheduler_task.cancel()
     try:
-        await polling_task
+        await scheduler_task
     except asyncio.CancelledError:
-        print("🤖 Bot polling stopped")
+        print("⏰ Scheduler stopped")
+    
+    # 3. Остановка бота
+    # polling_task.cancel()
+    # try:
+    #     await polling_task
+    # except asyncio.CancelledError:
+    #     print("🤖 Bot polling stopped")
 
     # 4. Отключение БД
     # Обычно Motor закрывать не обязательно при выходе, но хорошим тоном считается