Fix test failures and workload/websocket behavior

backend/app/main.py

@@ -1,3 +1,4 @@
+import os
 from contextlib import asynccontextmanager
 from datetime import datetime
 from fastapi import FastAPI, Request, APIRouter
@@ -16,11 +17,16 @@ from app.core.deprecation import DeprecationMiddleware
 @asynccontextmanager
 async def lifespan(app: FastAPI):
     """Manage application lifespan events."""
+    testing = os.environ.get("TESTING", "").lower() in ("true", "1", "yes")
+    scheduler_disabled = os.environ.get("DISABLE_SCHEDULER", "").lower() in ("true", "1", "yes")
+    start_background_jobs = not testing and not scheduler_disabled
     # Startup
-    start_scheduler()
+    if start_background_jobs:
+        start_scheduler()
     yield
     # Shutdown
-    shutdown_scheduler()
+    if start_background_jobs:
+        shutdown_scheduler()
 
 
 from app.api.auth import router as auth_router