refactor(ws): rename agent_ids to scout_ids in device_hello frame

WsDeviceHello.agent_ids → scout_ids in Pydantic schema,
device_ws.py handler, and all test fixtures (test_device_ws,
test_ws_unified, test_memory_middleware). Also fixes stale
CloudAgentConfig reference in gmail.py docstring.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/api/routes/device_ws.py

@@ -9,7 +9,7 @@ available during the WebSocket handshake).
 
 Protocol:
   1. Client connects → JWT validated → connection accepted.
-  2. Client sends ``device_hello`` frame: ``{ type, device_id, agent_ids }``.
+  2. Client sends ``device_hello`` frame: ``{ type, device_id, scout_ids }``.
   3. Backend registers the connection in ``DeviceConnectionManager``.
   4. Session enters message dispatch loop + heartbeat.
 
@@ -100,7 +100,7 @@ async def device_ws(websocket: WebSocket) -> None:
         if hello.get("type") != WsFrameType.device_hello:
             raise ValueError("expected device_hello as first frame")
         device_id: str = hello["device_id"]
-        agent_ids: list[str] = hello.get("agent_ids", [])
+        scout_ids: list[str] = hello.get("scout_ids", [])
     except (KeyError, ValueError, json.JSONDecodeError) as exc:
         logger.warning("device_ws: invalid device_hello from user=%s: %s", user_id, exc)
         await websocket.close(code=1008)
@@ -109,10 +109,10 @@ async def device_ws(websocket: WebSocket) -> None:
     # ── 3. Register connection ────────────────────────────────────────
     device_manager.register(user_id, device_id, websocket)
     logger.info(
-        "device_ws: connected user=%s device=%s agents=%s",
+        "device_ws: connected user=%s device=%s scouts=%s",
         user_id,
         device_id,
-        agent_ids,
+        scout_ids,
     )
 
     # Trigger any overdue agent runs now that the device is connected.

app/integrations/gmail.py

@@ -8,7 +8,7 @@ blocking the event loop.
 Token refresh is handled transparently: when the stored access token has
 expired, ``google.auth.transport.requests.Request`` will use the refresh
 token to obtain a fresh one.  The caller is responsible for persisting
-any refreshed credentials back to ``CloudAgentConfig.oauth_token_encrypted``
+any refreshed credentials back to ``CloudScoutConfig.oauth_token_encrypted``
 (see ``agent_runner.run_cloud_agent``).
 
 Credential dict shape (Google OAuth2):

app/schemas/__init__.py

@@ -147,7 +147,7 @@ class WsDeviceHello(BaseModel):
 
     type: Literal[WsFrameType.device_hello] = WsFrameType.device_hello
     device_id: str
-    agent_ids: list[str] = Field(default_factory=list)
+    scout_ids: list[str] = Field(default_factory=list)