fix: reconcile reused wechat agent sessions

wechat-mp.mjs

@@ -1658,6 +1658,7 @@ export function createWechatMpService({
           tolerateInvalidWorkingDir: true,
         },
       );
+<<<<<<< HEAD
       const routeHasTools = await sessionHasRequiredTools(
         fetchForSession,
         existingRoute.agentSessionId,
@@ -1694,9 +1695,9 @@ export function createWechatMpService({
       throw new Error('公众号专属 Agent 会话创建失败');
     }
 
-    if (!startAgentSession && typeof userAuth.registerAgentSession === 'function') {
+    // `/agent/start` already persists the owning user and goosed node via the
-      await userAuth.registerAgentSession(userId, sessionId);
+    // portal proxy. Re-registering here without the node can overwrite the
-    }
+    // correct mapping back to node 0 in multi-goosed production.
     await reconcileAgentSession(
       (pathname, init) => fetchForSession(sessionId, pathname, init),
       sessionId,