test(T05): contact router, rental router, email service, rate limiting tests + retry queue

backend/app/routers/contact.py

@@ -35,14 +35,15 @@ async def create_contact(
 
     email_service = EmailService()
     try:
-        await email_service.send_contact_email({
+        sent = await email_service.send_contact_email({
             "name": payload.name,
             "email": str(payload.email),
             "phone": payload.phone,
             "message": payload.message,
-        })
-        contact.email_sent = True
-        await db.commit()
+        }, db=db)
+        if sent:
+            contact.email_sent = True
+            await db.commit()
     except Exception:
         pass
 

backend/app/routers/rental_requests.py

@@ -133,6 +133,7 @@ async def create_rental_request(
             reference_number=ref_number,
             event_name=payload.event_name,
             items=items_data,
+            db=db,
         )
     except Exception:
         # Email failure should not affect response