refactor(auth): centralize login status sync

src/app/auth/auth-screen.tsx

@@ -9,7 +9,6 @@ import { useRouter } from "next/navigation";
 
 import { MobileShell } from "@/app/_components/core";
 import { useAuthDispatch, useAuthState } from "@/stores/auth/auth-context";
-import { useUserDispatch } from "@/stores/user/user-context";
 import { ROUTES } from "@/router/routes";
 
 import { AuthBackground, AuthPanel } from "./components";
@@ -18,10 +17,9 @@ import styles from "./components/auth-screen.module.css";
 export function AuthScreen() {
   const state = useAuthState();
   const authDispatch = useAuthDispatch();
-  const userDispatch = useUserDispatch();
   const router = useRouter();
 
-  // 邮箱登录成功 → 通知 User + 跳转
+  // 邮箱登录成功 → 跳转；User hydrate 由根级 <UserAuthSync /> 监听 loginStatus 变化处理。
   // 用 pendingRedirect flag（不是 useRef transition detection）——
   // re-mount 时 flag 在 auth context 里持久，区分"刚按了"和"re-visit"准确无误。
   useEffect(() => {
@@ -37,16 +35,9 @@ export function AuthScreen() {
         "[auth-screen] useEffect → router.replace(/chat) [via pendingRedirect flag]",
       );
       authDispatch({ type: "AuthClearPendingRedirect" });
-      userDispatch({ type: "UserInit" });
       router.replace(ROUTES.chat);
     }
-  }, [
-    state.loginStatus,
-    state.pendingRedirect,
-    authDispatch,
-    userDispatch,
-    router,
-  ]);
+  }, [state.loginStatus, state.pendingRedirect, authDispatch, router]);
 
   return (
     <MobileShell>