test: 添加完整测试套件（52 个文件，326 个用例）

基于 Vitest 搭建测试基础设施，覆盖后端纯函数、API 路由、
前端 hooks、UI 组件和页面级集成测试。

src/app/panic/page.test.tsx

@@ -0,0 +1,100 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen, fireEvent, waitFor } from "@testing-library/react";
+import React from "react";
+import { ToastContext, type ToastContextValue } from "@/hooks/useToast";
+
+vi.mock("next/navigation", () => ({
+  useRouter: () => ({
+    push: vi.fn(),
+    back: vi.fn(),
+  }),
+}));
+
+vi.mock("@/lib/userId", () => ({
+  getUserId: vi.fn().mockReturnValue("user-1"),
+  getCachedPreferences: vi.fn().mockReturnValue({}),
+}));
+
+vi.mock("@/lib/sceneConfig", () => ({
+  SCENES: ["eat", "drinks"],
+  getSceneConfig: vi.fn().mockReturnValue({
+    key: "eat",
+    label: "餐厅",
+    emoji: "🍜",
+    verb: "吃",
+    poiTypes: "050000",
+    defaultImage: "",
+    hotTags: ["火锅", "日料", "烧烤"],
+    priceOptions: [{ label: "不限", value: "any" }],
+    tagLabel: "口味",
+    tagPlaceholder: "想吃什么？",
+    loadingText: "正在搜索...",
+    emptyError: "没找到",
+    subtitle: "一起选餐厅",
+    inviteText: "邀请你",
+    shareTitle: "分享",
+    shareText: "一起来",
+    qrSubtitle: "扫码加入",
+  }),
+}));
+
+vi.mock("@/hooks/useGeolocation", () => ({
+  useGeolocation: vi.fn().mockReturnValue({
+    status: "success",
+    coords: { lat: 31.2, lng: 121.4 },
+    locationName: "上海",
+    retry: vi.fn(),
+  }),
+}));
+
+vi.mock("@/lib/room", () => ({
+  joinRoom: vi.fn().mockResolvedValue(undefined),
+}));
+
+const mockFetch = vi.fn().mockResolvedValue({
+  ok: true,
+  json: () => Promise.resolve({ suggestions: [] }),
+});
+vi.stubGlobal("fetch", mockFetch);
+
+import PanicPage from "./page";
+
+const toastCtx: ToastContextValue = { show: vi.fn() };
+
+function renderPage() {
+  return render(
+    React.createElement(
+      ToastContext.Provider,
+      { value: toastCtx },
+      React.createElement(PanicPage),
+    ),
+  );
+}
+
+beforeEach(() => {
+  vi.clearAllMocks();
+});
+
+describe("PanicPage", () => {
+  it("renders page title", () => {
+    renderPage();
+    expect(screen.getByText("极速救场")).toBeInTheDocument();
+  });
+
+  it("renders location search input", () => {
+    renderPage();
+    expect(screen.getByPlaceholderText(/搜索位置/)).toBeInTheDocument();
+  });
+
+  it("renders distance options", () => {
+    renderPage();
+    expect(screen.getByText("1km")).toBeInTheDocument();
+    expect(screen.getByText("3km")).toBeInTheDocument();
+    expect(screen.getByText("5km")).toBeInTheDocument();
+  });
+
+  it("renders scene selector with labels", () => {
+    renderPage();
+    expect(screen.getAllByText("餐厅").length).toBeGreaterThanOrEqual(1);
+  });
+});