refactor(chat): decouple chat state from auth and gate quota alerts to guests

- Remove ChatAuthStatusChanged dispatch from auth login flow; chat screen now subscribes directly to auth state machine (loginStatus) to derive isGuest and drive WS lifecycle
- Gate quota-exceeded and warning dialogs to guests only (non-guests have no message limit)
- Dispatch ChatLoadMoreHistory for non-guest initial load vs ChatInit for guests
- Fix AppConstants import path from @/core/constants/app_constants to @/core/app_constants
- Add defensive isGuest checks in quota effects to prevent non-guest quota triggers

src/app/auth/components/auth-legal-text.tsx

@@ -13,7 +13,7 @@
  */
 import { useState } from "react";
 
-import { AppConstants } from "@/core/constants/app_constants";
+import { AppConstants } from "@/core/app_constants";
 
 import styles from "./auth-legal-text.module.css";
 

src/app/auth/components/auth-screen.tsx

@@ -10,7 +10,6 @@ import { useRouter } from "next/navigation";
 import { MobileShell } from "@/app/_components/core/mobile-shell";
 
 import { useAuthDispatch, useAuthState } from "@/stores/auth/auth-context";
-import { useChatDispatch } from "@/stores/chat/chat-context";
 import { useUserDispatch } from "@/stores/user/user-context";
 import { ROUTES } from "@/router/routes";
 import styles from "./auth-screen.module.css";
@@ -22,15 +21,14 @@ export function AuthScreen() {
   // ===== 鉴权路由跳转已由 src/router/proxy.ts 集中处理 =====
   // 本组件只负责：
   //   1. 渲染登录 UI
-  //   2. 邮箱登录成功 → 初始化 chat/user store + navigate 到 /chat（业务层动作）
+  //   2. 邮箱登录成功 → 初始化 user store + navigate 到 /chat（业务层动作）
 
   const state = useAuthState();
   const authDispatch = useAuthDispatch();
-  const chatDispatch = useChatDispatch();
   const userDispatch = useUserDispatch();
   const router = useRouter();
 
-  // 邮箱登录成功 → 通知 Chat + User + 跳转
+  // 邮箱登录成功 → 通知 User + 跳转
   // 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(() => {
@@ -46,7 +44,6 @@ export function AuthScreen() {
         "[auth-screen] useEffect → router.replace(/chat) [via pendingRedirect flag]",
       );
       authDispatch({ type: "AuthClearPendingRedirect" });
-      chatDispatch({ type: "ChatAuthStatusChanged" });
       userDispatch({ type: "UserInit" });
       router.replace(ROUTES.chat);
     }
@@ -54,7 +51,6 @@ export function AuthScreen() {
     state.loginStatus,
     state.pendingRedirect,
     authDispatch,
-    chatDispatch,
     userDispatch,
     router,
   ]);

src/app/chat/components/chat-screen.tsx

@@ -5,24 +5,43 @@
  * 原始 Dart: lib/ui/chat/chat_screen.dart（172 行）
  *
  * 职责（本文件）：
+ *   - **订阅 auth 状态机**（loginStatus）——
+ *     - 派生 isGuest / 驱动 WS 生命周期 / 驱动初次加载（按 loginStatus 选 ChatInit vs ChatLoadMoreHistory）
+ *     - 驱动历史加载
  *   - 屏幕生命周期事件（init / visible / invisible）
- *   - 配额告警监听（quotaExceededTrigger + warningThreshold）
+ *   - 配额告警监听（**仅**游客 —— "非游客无消息限制"业务事实）
+ *   - WebSocket 生命周期管理（基于 auth 状态机的 loginStatus）
  *   - 渲染骨架（背景 + 顶部栏 + 消息区 + 输入栏）
  *
  * 子组件职责：
  *   - ChatHeader：顶部栏（游客 banner / 菜单按钮）
  *   - ChatArea：消息列表
  *   - ChatInputBar：输入栏（文字 + 发送 + More）
- *   - QuotaDialog：配额告警弹窗
+ *   - QuotaDialog：配额告警弹窗（**仅**游客）
  *   - PwaInstallOverlay：PWA 安装提示触发器
  *   - BrowserHintOverlay：浏览器提示
  *   - CharacterIntro：角色介绍卡片（首屏）
+ *
+ * **鉴权解耦**：
+ *   chat 机器**不**感知鉴权 —— isGuest 在此派生自 `auth.loginStatus === "guest"`。
+ *   chat 机器**不**管 WebSocket 生命周期 —— 由此 useEffect 监听 loginStatus 驱动。
+ *
+ * **配额（**仅**游客）**：
+ *   - 游客：派 ChatInit → readInitData 调 ChatStorage → onDone 条件赋
+ *   - 非游客：派 ChatLoadMoreHistory（无配额 init）—— "非游客无消息限制"业务事实
  */
 import { useEffect, useRef, useState } from "react";
 import Image from "next/image";
 
+import { useAuthState } from "@/stores/auth/auth-context";
+import type { LoginStatus } from "@/models/auth/login-status";
+import { AuthStorage } from "@/data/storage/auth/auth_storage";
 import { useChatDispatch, useChatState } from "@/stores/chat/chat-context";
 import { GuestChatQuota } from "@/stores/chat";
+import {
+  ChatWebSocket,
+  createChatWebSocket,
+} from "@/core/net/chat-websocket";
 
 import { MobileShell } from "@/app/_components/core/mobile-shell";
 
@@ -34,25 +53,154 @@ import { PwaInstallOverlay } from "./pwa-install-overlay";
 import { QuotaDialog } from "./quota-dialog";
 import styles from "./chat-screen.module.css";
 
+/**
+ * 派生 isGuest —— 单一来源：`auth.loginStatus`
+ */
+function deriveIsGuest(loginStatus: LoginStatus): boolean {
+  return loginStatus === "guest";
+}
+
+/**
+ * 拿 WebSocket token —— 按 loginStatus 选 loginToken 或 guestToken
+ */
+async function getWsToken(
+  loginStatus: LoginStatus,
+): Promise<string | null> {
+  if (loginStatus === "notLoggedIn") return null;
+  const storage = AuthStorage.getInstance();
+  if (loginStatus === "guest") {
+    const r = await storage.getGuestToken();
+    return r.success ? r.data : null;
+  }
+  // email / google / facebook / apple：都用业务 loginToken（OAuth sync 写下的）
+  const r = await storage.getLoginToken();
+  return r.success ? r.data : null;
+}
+
+/**
+ * 按 loginStatus 派初次加载事件（**仅**游客派 ChatInit —— 配额 init）
+ */
+function dispatchInitialLoad(
+  loginStatus: LoginStatus,
+  chatDispatch: ReturnType<typeof useChatDispatch>,
+): void {
+  if (loginStatus === "guest") {
+    chatDispatch({ type: "ChatInit" }); // 拉本地消息 + 初始化配额
+  } else if (loginStatus !== "notLoggedIn") {
+    chatDispatch({ type: "ChatLoadMoreHistory" }); // 拉服务器端首屏（**无**配额 init）
+  }
+}
+
 export function ChatScreen() {
   const state = useChatState();
-  const dispatch = useChatDispatch();
+  const authState = useAuthState();
+  const chatDispatch = useChatDispatch();
+
+  // isGuest 派生（chat-screen 是**唯一**知道这个值的地方 —— chat 机器无 isGuest 字段）
+  const isGuest = deriveIsGuest(authState.loginStatus);
 
   const [quotaDialogOpen, setQuotaDialogOpen] = useState(false);
   const [quotaExhausted, setQuotaExhausted] = useState(false);
 
-  // 屏幕生命周期
+  // ─────────────────────────────────────────────────────────────
+  // 屏幕生命周期 —— mount 时按 loginStatus 派初次加载
+  // ─────────────────────────────────────────────────────────────
   useEffect(() => {
-    dispatch({ type: "ChatInit" });
-    dispatch({ type: "ChatScreenVisible" });
+    chatDispatch({ type: "ChatScreenVisible" });
+    dispatchInitialLoad(authState.loginStatus, chatDispatch);
     return () => {
-      dispatch({ type: "ChatScreenInvisible" });
+      chatDispatch({ type: "ChatScreenInvisible" });
     };
-  }, [dispatch]);
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [chatDispatch]);
+  // 注：mount useEffect 故意**不**依赖 loginStatus —— 首次 mount 时机是固定的
+  //     （"用户进 /chat 那一刻"），loginStatus 由 splash/auth-screen 提前 settle。
+  //     loginStatus 后续变化由下方"副作用 ②" 统一处理。
 
-  // 配额耗尽触发器
+  // ─────────────────────────────────────────────────────────────
+  // 核心副作用 ①：loginStatus 变化 → 连/断 WebSocket
+  // ─────────────────────────────────────────────────────────────
+  const wsRef = useRef<ChatWebSocket | null>(null);
+
+  useEffect(() => {
+    let cancelled = false;
+
+    void (async () => {
+      if (authState.loginStatus === "notLoggedIn") {
+        // 登出 / 未登录：断开 WS
+        if (wsRef.current) {
+          wsRef.current.disconnect();
+          wsRef.current = null;
+        }
+        return;
+      }
+
+      // 已登录：拿 token → 连 WS
+      const token = await getWsToken(authState.loginStatus);
+      if (cancelled || !token) return;
+
+      // 清理旧连接（如有）
+      if (wsRef.current) {
+        wsRef.current.disconnect();
+        wsRef.current = null;
+      }
+
+      const ws = createChatWebSocket(token);
+      ws.onConnected = (userId) => {
+        chatDispatch({ type: "ChatWebSocketConnected", userId });
+      };
+      ws.onSentence = (p) => {
+        chatDispatch({
+          type: "ChatAISentenceReceived",
+          index: p.index,
+          text: p.text,
+          total: p.total,
+          done: p.done,
+        });
+      };
+      ws.onError = (msg) => {
+        chatDispatch({ type: "ChatWebSocketError", errorMessage: msg });
+      };
+      ws.connect();
+      wsRef.current = ws;
+    })();
+
+    return () => {
+      cancelled = true;
+      if (wsRef.current) {
+        wsRef.current.disconnect();
+        wsRef.current = null;
+      }
+    };
+  }, [authState.loginStatus, chatDispatch]);
+
+  // ─────────────────────────────────────────────────────────────
+  // 副作用 ②：loginStatus 变化 → 重新加载
+  //
+  // 规则：
+  //   - 首次 mount（prev === null）→ 由 mount useEffect 统一处理
+  //   - "notLoggedIn" → 不加载
+  //   - 登录态变化（guest→email 等）→ 重新加载
+  //     - 游客派 ChatInit（拉本地 + **初始化配额**）
+  //     - 非游客派 ChatLoadMoreHistory（拉服务器端首屏，**无**配额 init）
+  // ─────────────────────────────────────────────────────────────
+  const prevLoginStatusRef = useRef<LoginStatus | null>(null);
+  useEffect(() => {
+    const prev = prevLoginStatusRef.current;
+    prevLoginStatusRef.current = authState.loginStatus;
+    if (prev === null) return; // 首次 mount 由 mount useEffect 处理
+    if (authState.loginStatus === "notLoggedIn") return;
+    if (prev !== authState.loginStatus) {
+      dispatchInitialLoad(authState.loginStatus, chatDispatch);
+    }
+  }, [authState.loginStatus, chatDispatch]);
+
+  // ─────────────────────────────────────────────────────────────
+  // 配额耗尽触发器（**仅**游客 —— "非游客无消息限制"）
+  // ─────────────────────────────────────────────────────────────
   const prevTriggerRef = useRef(state.quotaExceededTrigger);
   useEffect(() => {
+    if (!isGuest) return; // ← 防御：非游客 backend 不会发 ChatQuotaExceeded
     if (
       state.quotaExceededTrigger !== prevTriggerRef.current &&
       state.quotaExceededTrigger > 0
@@ -61,13 +209,13 @@ export function ChatScreen() {
       setQuotaDialogOpen(true);
     }
     prevTriggerRef.current = state.quotaExceededTrigger;
-  }, [state.quotaExceededTrigger]);
+  }, [state.quotaExceededTrigger, isGuest]);
 
-  // 配额警告（剩余 = 5）
+  // 配额警告（剩余 = 5）—— **仅**游客
   const prevRemainingRef = useRef(state.guestRemainingQuota);
   useEffect(() => {
     if (
-      state.isGuest &&
+      isGuest && // ← 派生自 auth.loginStatus
       state.guestRemainingQuota === GuestChatQuota.warningThreshold &&
       prevRemainingRef.current !== state.guestRemainingQuota
     ) {
@@ -75,7 +223,7 @@ export function ChatScreen() {
       setQuotaDialogOpen(true);
     }
     prevRemainingRef.current = state.guestRemainingQuota;
-  }, [state.guestRemainingQuota, state.isGuest]);
+  }, [state.guestRemainingQuota, isGuest]);
 
   return (
     <MobileShell>
@@ -92,12 +240,13 @@ export function ChatScreen() {
         </div>
 
         <div className={styles.layout}>
-          <ChatHeader isGuest={state.isGuest} />
+          {/* isGuest 派生自 auth.loginStatus */}
+          <ChatHeader isGuest={isGuest} />
 
           <ChatArea
             messages={state.messages}
             isReplyingAI={state.isReplyingAI}
-            isGuest={state.isGuest}
+            isGuest={isGuest}
           />
 
           <ChatInputBar disabled={state.isReplyingAI} />
@@ -109,7 +258,7 @@ export function ChatScreen() {
         {/* PWA 安装提示触发器（无可见 UI，3.5s 后弹 dialog） */}
         <PwaInstallOverlay />
 
-        {/* 配额告警弹窗 */}
+        {/* 配额告警弹窗（**仅**游客，gate 在 isGuest） */}
         <QuotaDialog
           open={quotaDialogOpen}
           onClose={() => setQuotaDialogOpen(false)}

src/app/layout.tsx

@@ -1,6 +1,6 @@
 import type { Metadata, Viewport } from "next";
 import { SessionProvider } from "@/providers/session-provider";
-import { geistSans, geistMono, athelas } from "@/lib/fonts";
+import { geistSans, geistMono, athelas } from "@/core/fonts";
 import "./globals.css";
 
 import { RootProviders } from "@/providers/root-providers";

src/app/sidebar/components/sidebar-screen.tsx

@@ -8,7 +8,6 @@ import { MobileShell } from "@/app/_components/core/mobile-shell";
 import { SettingsSection } from "@/app/_components/core/settings-section";
 import { useUserDispatch, useUserState } from "@/stores/user/user-context";
 import { useAuthDispatch } from "@/stores/auth/auth-context";
-import { useChatDispatch } from "@/stores/chat/chat-context";
 import { ROUTES } from "@/router/routes";
 
 import type { UserView } from "@/models/user/user";
@@ -23,7 +22,6 @@ import styles from "./sidebar-screen.module.css";
 export function SidebarScreen() {
   const user = useUserState();
   const userDispatch = useUserDispatch();
-  const chatDispatch = useChatDispatch();
   const authDispatch = useAuthDispatch();
   const router = useRouter();
 
@@ -34,17 +32,18 @@ export function SidebarScreen() {
 
   // 等价 Dart: BlocConsumer<UserBloc> 的 listener（profile_view.dart:24-34）
   // 仅在 currentUser 由非 null 跳到 null 时触发清理
+  // 注：chat 机器**不**再需要 `ChatAuthStatusChanged` 通知（已**删**）—— chat-screen
+  //     通过 `useAuthState()` 主动订阅 loginStatus；这里只需重置 auth + 跳 /chat
   const prevUserRef = useRef<UserView | null>(user.currentUser);
   useEffect(() => {
     const wasLoggedIn = prevUserRef.current != null;
     const isNowLoggedOut = user.currentUser == null;
     prevUserRef.current = user.currentUser;
     if (wasLoggedIn && isNowLoggedOut) {
-      chatDispatch({ type: "ChatAuthStatusChanged" });
       authDispatch({ type: "AuthReset" });
       router.replace(ROUTES.chat);
     }
-  }, [user.currentUser, chatDispatch, authDispatch, router]);
+  }, [user.currentUser, authDispatch, router]);
 
   return (
     <MobileShell>

src/app/splash/components/splash-screen.tsx

@@ -5,7 +5,6 @@ import { useRouter } from "next/navigation";
 
 import { MobileShell } from "@/app/_components/core/mobile-shell";
 import { useAuthDispatch, useAuthState } from "@/stores/auth/auth-context";
-import { useChatDispatch } from "@/stores/chat/chat-context";
 import { useUserDispatch } from "@/stores/user/user-context";
 import { AuthStorage } from "@/data/storage/auth/auth_storage";
 import { ROUTES } from "@/router/routes";
@@ -20,7 +19,6 @@ export function SplashScreen() {
   const router = useRouter();
   const state = useAuthState();
   const authDispatch = useAuthDispatch();
-  const chatDispatch = useChatDispatch();
   const userDispatch = useUserDispatch();
 
   // ─────────────────────────────────────────────────────────────
@@ -66,7 +64,6 @@ export function SplashScreen() {
         "[splash] useEffect ② → router.replace(/chat) [via pendingRedirect flag]",
       );
       authDispatch({ type: "AuthClearPendingRedirect" });
-      chatDispatch({ type: "ChatAuthStatusChanged" });
       userDispatch({ type: "UserInit" });
       router.replace(ROUTES.chat);
     }
@@ -74,7 +71,6 @@ export function SplashScreen() {
     state.loginStatus,
     state.pendingRedirect,
     authDispatch,
-    chatDispatch,
     userDispatch,
     router,
   ]);