don't use worker pool for file listing

src/connectors/google_drive/connector.py

@@ -218,7 +218,12 @@ class GoogleDriveConnector(BaseConnector):
         return self.service.changes().getStartPageToken().execute()['startPageToken']
     
     async def list_files(self, page_token: Optional[str] = None, limit: Optional[int] = None) -> Dict[str, Any]:
-        """List all supported files in Google Drive"""
+        """List all supported files in Google Drive.
+
+        Uses a thread pool (not the shared process pool) to avoid issues with
+        Google API clients in forked processes and adds light retries for
+        transient BrokenPipe/connection errors.
+        """
         if not self._authenticated:
             raise ValueError("Not authenticated")
 
@@ -229,23 +234,35 @@ class GoogleDriveConnector(BaseConnector):
         # Use provided limit or default to 100, max 1000 (Google Drive API limit)
         page_size = min(limit or 100, 1000)
 
+        def _sync_list_files_inner():
+            import time
+            attempts = 0
+            max_attempts = 3
+            backoff = 1.0
+            while True:
+                try:
+                    return self.service.files().list(
+                        q=query,
+                        pageSize=page_size,
+                        pageToken=page_token,
+                        fields="nextPageToken, files(id, name, mimeType, modifiedTime, createdTime, webViewLink, permissions, owners)"
+                    ).execute()
+                except Exception as e:
+                    attempts += 1
+                    is_broken_pipe = isinstance(e, BrokenPipeError) or (
+                        isinstance(e, OSError) and getattr(e, 'errno', None) == 32
+                    )
+                    if attempts < max_attempts and is_broken_pipe:
+                        time.sleep(backoff)
+                        backoff = min(4.0, backoff * 2)
+                        continue
+                    raise
+
         try:
-            # Run the blocking Google API call in a thread pool to avoid blocking the event loop
+            # Offload blocking HTTP call to default ThreadPoolExecutor
             import asyncio
             loop = asyncio.get_event_loop()
-            
+            results = await loop.run_in_executor(None, _sync_list_files_inner)
-            # Use the same process pool as docling processing
-            from utils.process_pool import process_pool
-            results = await loop.run_in_executor(
-                process_pool, 
-                _sync_list_files_worker, 
-                self.oauth.client_id,
-                self.oauth.client_secret,
-                self.oauth.token_file,
-                query, 
-                page_token,  # page_token should come before page_size
-                page_size
-            )
 
             files = []
             for file in results.get('files', []):