fix(tasks): increase redis lock timeout and expiration for write_message_task

- Increase lock expiration time from 120 to 600 seconds (5 minutes)
- Increase lock timeout from 300 to 3600 seconds (1 hour)
- Prevents premature lock release during long-running memory write operations

api/app/tasks.py

@@ -1180,8 +1180,8 @@ def write_message_task(
         lock = RedisFairLock(
             key=f"memory_write:{end_user_id}",
             redis_client=redis_client,
-            expire=120,
+            expire=600,
-            timeout=300,
+            timeout=3600,
             auto_renewal=True,
         )
         if not lock.acquire():