refactor: 前端架构重构 — hook拆分、组件拆分、类型筛选器动态化、Meta API

- 后端新增 GET /api/meta 端点（checkerRegistry.supportedTypes）及 MetaResponse 类型
- 前端 hook 拆分为 use-queries.ts（全局查询+useMeta）和 use-target-detail.ts（Drawer状态）
- TargetDetailDrawer 拆分为 OverviewTab + HistoryTab + history-table-columns + stats.ts
- 类型筛选器由 meta API 动态驱动，删除 target-type-display 静态映射
- 列定义改为工厂函数 createTargetTableColumns(checkerTypes)，TargetGroup 新增 columns prop
- 修复 StatusDonut key、StatusBar maxSlots prop、TrendChart 移除 loading prop
- 补充 utils/time、utils/stats、动态列工厂测试，删除旧 mapping 测试
- 同步 delta specs 到主 specs，归档 frontend-architecture-refactor change

tests/web/utils/time.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, test } from "bun:test";
+
+import { subtractHours } from "../../../src/web/utils/time";
+
+describe("subtractHours", () => {
+  test("正常扣减小时", () => {
+    const result = subtractHours(new Date("2025-01-15T12:00:00.000Z"), 3);
+
+    expect(result.toISOString()).toBe("2025-01-15T09:00:00.000Z");
+  });
+
+  test("跨天扣减", () => {
+    const result = subtractHours(new Date("2025-01-15T02:00:00.000Z"), 6);
+
+    expect(result.toISOString()).toBe("2025-01-14T20:00:00.000Z");
+  });
+
+  test("跨月扣减", () => {
+    const result = subtractHours(new Date("2025-03-01T01:00:00.000Z"), 2);
+
+    expect(result.toISOString()).toBe("2025-02-28T23:00:00.000Z");
+  });
+
+  test("扣减 0 小时返回相同时间", () => {
+    const result = subtractHours(new Date("2025-01-15T12:00:00.000Z"), 0);
+
+    expect(result.toISOString()).toBe("2025-01-15T12:00:00.000Z");
+  });
+});