feat(chat): migrate chat to backend API

app/(order)/chat/page.tsx

@@ -3,15 +3,33 @@
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar"
 import { Badge } from "@/components/ui/badge"
 import { Card, CardContent } from "@/components/ui/card"
+import { listChatSessions } from "@/lib/api"
 import { useAuthStore } from "@/store/auth"
-import { useChatStore } from "@/store/chat"
 import { Lock, MessageSquare } from "lucide-react"
 import Link from "next/link"
+import { useEffect, useState } from "react"
 
 export default function ChatListPage() {
-  const sessions = useChatStore((state) => state.sessions)
+  const [sessions, setSessions] = useState<Awaited<ReturnType<typeof listChatSessions>>>([])
   const userId = useAuthStore((state) => state.user?.id)
 
+  useEffect(() => {
+    let cancelled = false
+
+    void (async () => {
+      try {
+        const result = await Promise.resolve(listChatSessions())
+        if (!cancelled) setSessions(result)
+      } catch {
+        if (!cancelled) setSessions([])
+      }
+    })()
+
+    return () => {
+      cancelled = true
+    }
+  }, [])
+
   return (
     <div className="container mx-auto max-w-2xl px-4 py-8 space-y-6">
       <h1 className="text-2xl font-bold">消息</h1>