fix: prevent agent debug from blocking chat

ai_knowledge_base_v2/apps/backend/app/services/model_service.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import asyncio
 import json
 from dataclasses import dataclass
 from typing import Any
@@ -93,6 +94,11 @@ class ModelClientService:
             "knowledgeIds": rag_result.knowledge_ids,
         }
 
+    @staticmethod
+    async def debug_model_async(model: ModelConfig, rag_result: RagResult, overrides: dict[str, Any]) -> dict[str, Any]:
+        """Run the blocking provider client outside the ASGI event loop."""
+        return await asyncio.to_thread(ModelClientService.debug_model, model, rag_result, overrides)
+
 
 def _mock_answer(rag_result: RagResult) -> str:
     if not rag_result.is_hit: