fix: register Linear tools in TOOLS_WITH_UI and make GraphQL calls async

- Add create_linear_issue, update_linear_issue, delete_linear_issue to
  TOOLS_WITH_UI so the HIL approval cards are correctly dispatched to
  the Linear tool-ui components (without this the interrupt cards were
  never rendered)
- Replace blocking requests.post with httpx.AsyncClient in
  LinearConnector.execute_graphql_query to avoid stalling the asyncio
  event loop during live streaming; remove now-unused requests import

surfsense_backend/app/connectors/linear_connector.py

@@ -10,7 +10,6 @@ from datetime import datetime
 from typing import Any
 
 import httpx
-import requests
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy.future import select
 
@@ -274,7 +273,10 @@ class LinearConnector:
         if variables:
             payload["variables"] = variables
 
-        response = requests.post(self.api_url, headers=headers, json=payload)
+        async with httpx.AsyncClient() as client:
+            response = await client.post(
+                self.api_url, headers=headers, json=payload, timeout=30.0
+            )
 
         if response.status_code == 200:
             return response.json()