Fix chat SSE events to match frontend protocol (result+done instead of success)

backend/api/demo.py

@@ -275,21 +275,27 @@ async def execute_query_stream(req: ExecuteQueryRequest):
 
             if attempt_success:
                 success = True
+                # Emit events matching the frontend's expected protocol
                 yield {"data": json.dumps({
-                    "type": "success",
+                    "type": "result",
                     "rows": rows,
                     "row_count": len(rows),
-                    "sql": generated_sql,
+                })}
+                yield {"data": json.dumps({
+                    "type": "done",
+                    "attempts": attempt,
                 })}
                 done = True
                 break
 
         total_reward = compute_episode_reward(all_step_rewards, success)
-        yield {"data": json.dumps({
-            "type": "rl_episode_end",
-            "total_reward": total_reward,
-            "success": success,
-        })}
+
+        if not success:
+            # All attempts exhausted without success
+            yield {"data": json.dumps({
+                "type": "error",
+                "message": "Agent exhausted all repair attempts",
+            })}
 
         # Record GEPA history
         gepa = get_gepa()