refactor: 后端架构加固 — 泛型化、批量查询、bootstrap 统一、路径修复与 pageSize 上限

- CheckerDefinition 泛型化，HTTP/Command checker 移除 resolved target 断言
- 新增 ProbeStore.getAllRecentSamples 消除 targets 路由 N+1 查询
- 统一 getAllTargetStats 与 getTargetStats 的 availability 精度
- Engine rejected 结果写入 internal error 记录，提升可观测性
- 新增 bootstrap.ts 统一 dev/production 启动序列
- dataDir 相对路径改为基于配置文件目录解析
- validatePagination 增加 pageSize 上限 200 校验
- 修复 ErrorBoundary override 标记
- 更新 README/DEVELOPMENT 文档，新增完整测试覆盖

tests/server/bootstrap.test.ts

@@ -0,0 +1,141 @@
+import { describe, expect, test } from "bun:test";
+
+import type { StaticAssets } from "../../src/server/app";
+import type { ResolvedConfig } from "../../src/server/checker/config-loader";
+import type { ProbeEngine } from "../../src/server/checker/engine";
+import type { ProbeStore } from "../../src/server/checker/store";
+import type { ResolvedTargetBase } from "../../src/server/checker/types";
+
+import { bootstrap, type BootstrapDependencies } from "../../src/server/bootstrap";
+
+type ShutdownSignal = "SIGINT" | "SIGTERM";
+
+const target: ResolvedTargetBase = {
+  group: "default",
+  intervalMs: 30000,
+  name: "test",
+  timeoutMs: 5000,
+  type: "command",
+};
+
+function createHarness(overrides: BootstrapDependencies = {}) {
+  const calls: string[] = [];
+  const shutdownHandlers = new Map<ShutdownSignal, () => void>();
+  const config: ResolvedConfig = {
+    configDir: "/tmp",
+    dataDir: "/tmp/dial-data",
+    host: "127.0.0.1",
+    maxConcurrentChecks: 3,
+    port: 3000,
+    retentionMs: 1000,
+    targets: [target],
+  };
+  const store = {
+    close() {
+      calls.push("store.close");
+    },
+    syncTargets(targets: ResolvedTargetBase[]) {
+      calls.push(`syncTargets:${targets.length}`);
+    },
+  } as unknown as ProbeStore;
+  const engine = {
+    start() {
+      calls.push("engine.start");
+    },
+    stop() {
+      calls.push("engine.stop");
+    },
+  } as unknown as ProbeEngine;
+
+  const dependencies: BootstrapDependencies = {
+    createEngine(actualStore, targets, maxConcurrentChecks, retentionMs) {
+      expect(actualStore).toBe(store);
+      calls.push(`createEngine:${targets.length}:${maxConcurrentChecks}:${retentionMs}`);
+      return engine;
+    },
+    createStore(dbPath) {
+      calls.push(`createStore:${dbPath}`);
+      return store;
+    },
+    exit(code) {
+      calls.push(`exit:${code}`);
+      throw new Error(`exit:${code}`);
+    },
+    loadConfig(configPath) {
+      calls.push(`loadConfig:${configPath}`);
+      return Promise.resolve(config);
+    },
+    logError(...data) {
+      calls.push(`logError:${String(data[1])}`);
+    },
+    onSignal(signal, handler) {
+      calls.push(`onSignal:${signal}`);
+      shutdownHandlers.set(signal, handler);
+    },
+    startServer(options) {
+      expect(options.config).toEqual({ host: config.host, port: config.port });
+      expect(options.store).toBe(store);
+      calls.push(`startServer:${options.mode}:${options.staticAssets ? "static" : "no-static"}`);
+    },
+    ...overrides,
+  };
+
+  return { calls, dependencies, shutdownHandlers };
+}
+
+describe("bootstrap", () => {
+  test("开发模式执行完整启动序列", async () => {
+    const { calls, dependencies } = createHarness();
+
+    await bootstrap({ configPath: "/tmp/probes.yaml", mode: "development" }, dependencies);
+
+    expect(calls).toEqual([
+      "loadConfig:/tmp/probes.yaml",
+      "createStore:/tmp/dial-data/probe.db",
+      "syncTargets:1",
+      "createEngine:1:3:1000",
+      "engine.start",
+      "onSignal:SIGINT",
+      "onSignal:SIGTERM",
+      "startServer:development:no-static",
+    ]);
+  });
+
+  test("生产模式传递 staticAssets", async () => {
+    const { calls, dependencies } = createHarness();
+    const staticAssets: StaticAssets = { files: {}, indexHtml: new Blob(["ok"]) };
+
+    await bootstrap({ configPath: "/tmp/probes.yaml", mode: "production", staticAssets }, dependencies);
+
+    expect(calls.at(-1)).toBe("startServer:production:static");
+  });
+
+  test("收到退出信号时停止 engine 并关闭 store", async () => {
+    const { calls, dependencies, shutdownHandlers } = createHarness();
+
+    await bootstrap({ configPath: "/tmp/probes.yaml", mode: "development" }, dependencies);
+
+    expect(() => shutdownHandlers.get("SIGINT")!()).toThrow("exit:0");
+
+    expect(calls.slice(-3)).toEqual(["engine.stop", "store.close", "exit:0"]);
+  });
+
+  test("启动失败时输出错误并以非零退出", async () => {
+    const { calls, dependencies } = createHarness({
+      loadConfig() {
+        return Promise.reject(new Error("bad config"));
+      },
+    });
+
+    let error: unknown;
+    try {
+      await bootstrap({ configPath: "/tmp/probes.yaml", mode: "development" }, dependencies);
+    } catch (caught) {
+      error = caught;
+    }
+
+    expect(error).toBeInstanceOf(Error);
+    expect((error as Error).message).toBe("exit:1");
+    expect(calls).toEqual(["logError:bad config", "exit:1"]);
+  });
+});