fix(talk): 实时通道连接失败时透出错误原因

- 新增 connect_error 监听，dispatch talk:error 携带原因

- 避免握手被拒时前端无任何提示

src/utils/talkSocket.ts

@@ -45,6 +45,8 @@ let CurrentToken = ''
 let HeartbeatTimer: ReturnType<typeof setInterval> | null = null
 /** 是否已针对 401 重连过一次（防止无限刷新令牌） */
 let ReauthAttempted = false
+/** 本次连接周期是否已提示过连接失败（重连期间不重复弹提示） */
+let ConnectErrorReported = false
 /** 连接中 Promise（并发调用去重） */
 let Connecting: Promise<Socket | null> | null = null
 
@@ -112,6 +114,7 @@ async function HandleUnauthorized(): Promise<void> {
 function BindCoreEvents(socket: Socket): void {
   socket.on('connect', () => {
     ReauthAttempted = false
+    ConnectErrorReported = false
     // 命名空间鉴权：auth.Token 已携带，仍按契约显式发一次 talk:auth
     socket.emit('talk:auth', { Token: CurrentToken })
     StartHeartbeat(socket)
@@ -119,6 +122,15 @@ function BindCoreEvents(socket: Socket): void {
   socket.on('disconnect', () => {
     StopHeartbeat()
   })
+  // 连接建立失败（如 CORS 被拒、网络不可达）：把原因透给页面，避免"什么都看不到"
+  socket.on('connect_error', (error: Error) => {
+    if (ConnectErrorReported) return
+    ConnectErrorReported = true
+    Dispatch('talk:error', {
+      code: 0,
+      msg: `Talk 实时通道连接失败：${error?.message || '未知原因'}（消息将不会实时到达）`,
+    })
+  })
   // 重连前刷新 auth，保证使用最新令牌
   socket.io.on('reconnect_attempt', () => {
     socket.auth = { Token: CurrentToken }
@@ -203,6 +215,7 @@ export function disconnectTalkSocket(): void {
     SocketInstance = null
   }
   ReauthAttempted = false
+  ConnectErrorReported = false
   CurrentToken = ''
   Connecting = null
 }