test: 重构测试体系 — 建立组件测试层、补充后端测试、清理低质量测试

- 新增 jsdom + @testing-library/react 组件测试环境
- 新增 12 个组件测试，覆盖所有前端组件
- 补充后端 middleware 和 helpers 单元测试
- 删除伪测试 use-target-detail-logic.test.ts
- 精简过度枚举的 color-threshold.test.ts
- 新增 bunfig.toml 配置测试 preload
- 更新 DEVELOPMENT.md 测试章节
- 安装 @types/jsdom 修复类型声明

tests/web/components/StatusBar.test.tsx

@@ -0,0 +1,31 @@
+import "../../../tests/web/test-utils";
+import { render } from "@testing-library/react";
+import { describe, expect, test } from "bun:test";
+
+import type { RecentSample } from "../../../src/shared/api";
+
+import { StatusBar } from "../../../src/web/components/StatusBar";
+
+describe("StatusBar", () => {
+  const now = new Date().toISOString();
+
+  const samples: RecentSample[] = [
+    { durationMs: 100, timestamp: now, up: true },
+    { durationMs: 150, timestamp: new Date(Date.now() - 60000).toISOString(), up: false },
+  ];
+
+  test("渲染不崩溃", () => {
+    const { container } = render(<StatusBar maxSlots={5} samples={samples} />);
+    expect(container.firstChild).not.toBeNull();
+  });
+
+  test("默认 maxSlots 不崩溃", () => {
+    const { container } = render(<StatusBar samples={samples} />);
+    expect(container.firstChild).not.toBeNull();
+  });
+
+  test("空 samples 不崩溃", () => {
+    const { container } = render(<StatusBar maxSlots={3} samples={[]} />);
+    expect(container.firstChild).not.toBeNull();
+  });
+});