fix: alembic reads DB URL from config.py (secrets file) not hardcoded alembic.ini

Authored by: Jack Levy

backend/alembic/env.py

@@ -10,8 +10,14 @@ import app.models  # noqa: F401 — registers all models with Base.metadata
 
 config = context.config
 
-# Override sqlalchemy.url from environment if set
+# Override sqlalchemy.url — prefer env var, then config.py (which reads secrets file)
 sync_url = os.environ.get("SYNC_DATABASE_URL")
+if not sync_url:
+    try:
+        from app.config import settings as app_settings
+        sync_url = app_settings.SYNC_DATABASE_URL
+    except Exception:
+        pass
 if sync_url:
     config.set_main_option("sqlalchemy.url", sync_url)