feat: 创建房间时支持自定义筛选条件（距离/人均/菜系）

替换硬编码搜索参数，用户可选择距离范围（1/3/5km）、
人均价格区间（50以下/50-100/100+）和菜系偏好（火锅、
日料、烧烤等），直接提升推荐质量。

src/app/api/room/create/route.ts

@@ -70,12 +70,42 @@ function mapPoiToRestaurant(poi: AmapPoiV5): Restaurant {
   };
 }
 
+function filterByPrice(
+  restaurants: Restaurant[],
+  priceRange: string,
+): Restaurant[] {
+  if (priceRange === "any") return restaurants;
+
+  return restaurants.filter((r) => {
+    if (r.price === "未知") return true;
+    const cost = parseInt(r.price.replace(/[¥￥]/g, ""), 10);
+    if (isNaN(cost)) return true;
+
+    switch (priceRange) {
+      case "under50":
+        return cost < 50;
+      case "50to100":
+        return cost >= 50 && cost <= 100;
+      case "over100":
+        return cost > 100;
+      default:
+        return true;
+    }
+  });
+}
+
 export async function POST(req: Request) {
   let restaurants: Restaurant[] = fallbackRestaurants;
 
   try {
     const body = await req.json();
-    const { lat, lng } = body;
+    const {
+      lat,
+      lng,
+      radius = 3000,
+      priceRange = "any",
+      cuisine = "不限",
+    } = body;
 
     if (lat && lng) {
       const apiKey = process.env.AMAP_API_KEY;
@@ -85,17 +115,25 @@ export async function POST(req: Request) {
         const url = new URL("https://restapi.amap.com/v5/place/around");
         url.searchParams.set("key", apiKey);
         url.searchParams.set("location", `${lng},${lat}`);
-        url.searchParams.set("radius", "3000");
+        url.searchParams.set("radius", String(radius));
         url.searchParams.set("types", "050000");
         url.searchParams.set("show_fields", "business,photos");
-        url.searchParams.set("page_size", "15");
         url.searchParams.set("sortrule", "weight");
 
+        const needsPriceFilter = priceRange !== "any";
+        url.searchParams.set("page_size", needsPriceFilter ? "25" : "15");
+
+        if (cuisine && cuisine !== "不限") {
+          url.searchParams.set("keywords", cuisine);
+        }
+
         const amapRes = await fetch(url.toString());
         const amapData = await amapRes.json();
 
         if (amapData.status === "1" && amapData.pois?.length > 0) {
-          restaurants = amapData.pois.map(mapPoiToRestaurant);
+          let results: Restaurant[] = amapData.pois.map(mapPoiToRestaurant);
+          results = filterByPrice(results, priceRange);
+          restaurants = results.slice(0, 15);
         }
       }
     }