refactor: 提取 buildNavUrl 工具函数，统一 room API 错误处理

- 将 MatchResult.tsx 和 profile/page.tsx 中重复的导航 URL 构建逻辑提取到 src/lib/navigation.ts
- 7 个 room API 路由从 return NextResponse.json({ error }, { status }) 统一改为 throw ApiError，由 apiHandler 统一捕获

src/app/api/room/[id]/reset/route.ts

@@ -1,7 +1,7 @@
 import { NextResponse } from "next/server";
 import { atomicUpdateRoom } from "@/lib/store";
 import { notify } from "@/lib/roomEvents";
-import { apiHandler } from "@/lib/api";
+import { apiHandler, ApiError } from "@/lib/api";
 
 export const POST = apiHandler(async (req, { params }) => {
   const { id } = await params;
@@ -27,12 +27,7 @@ export const POST = apiHandler(async (req, { params }) => {
     return data;
   });
 
-  if (!updated) {
-    return NextResponse.json(
-      { error: "房间不存在或已过期" },
-      { status: 404 },
-    );
-  }
+  if (!updated) throw new ApiError("房间不存在或已过期", 404);
 
   notify(id);