feat: 实现 NoWhatever 别说随便餐厅决策 Web App

- Framer Motion 卡片滑动 UI，带物理阻尼动画
- 多人房间系统，4位房间号 + SWR 实时轮询
- 高德地图 POI v5 API 搜索附近餐厅
- Web Share API 一键邀请，剪贴板降级方案
- SQLite/Prisma 持久化存储
- 移动端优先响应式设计 (Tailwind CSS)

src/app/room/[id]/page.tsx

@@ -0,0 +1,52 @@
+"use client";
+
+import { useEffect, useState } from "react";
+import { useParams } from "next/navigation";
+import TopNav from "@/components/TopNav";
+import SwipeDeck from "@/components/SwipeDeck";
+import { useRoomPolling } from "@/hooks/useRoomPolling";
+import { getUserId } from "@/lib/userId";
+
+export default function RoomPage() {
+  const params = useParams<{ id: string }>();
+  const roomId = params.id;
+
+  const [userId, setUserId] = useState("");
+  const [joined, setJoined] = useState(false);
+
+  const { userCount, match, restaurants } = useRoomPolling(roomId);
+
+  useEffect(() => {
+    const id = getUserId();
+    setUserId(id);
+
+    fetch(`/api/room/${roomId}/join`, {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({ userId: id }),
+    }).then(() => setJoined(true));
+  }, [roomId]);
+
+  const ready = joined && userId && restaurants.length > 0;
+
+  if (!ready) {
+    return (
+      <div className="flex h-dvh flex-col items-center justify-center gap-3 bg-background">
+        <div className="h-6 w-6 animate-spin rounded-full border-2 border-zinc-300 border-t-emerald-500" />
+        <p className="text-sm text-zinc-400">正在加载餐厅数据...</p>
+      </div>
+    );
+  }
+
+  return (
+    <div className="flex h-dvh flex-col bg-background">
+      <TopNav roomId={roomId} userCount={userCount} />
+      <SwipeDeck
+        restaurants={restaurants}
+        roomId={roomId}
+        userId={userId}
+        matchedRestaurantId={match}
+      />
+    </div>
+  );
+}