feat: 基础设施加固 — 修复构建、数据保留、错误边界、bundle 拆分

- 修复 build script 引用已删除的 registerCheckers，恢复生产构建
- 生产入口添加 SIGINT/SIGTERM 优雅关闭（与 dev.ts 一致）
- 新增 runtime.retention 配置（默认 7d），ProbeStore.prune() 定时清理过期数据
- parseDuration 扩展支持 h/d 单位
- 新增前端 ErrorBoundary 组件，防止渲染错误白屏
- Vite codeSplitting.groups 拆分 vendor chunks（业务代码 1180KB → 47KB）
- 同步 delta specs 到主规范

src/server/checker/config-loader.ts

@@ -15,6 +15,7 @@ const DEFAULT_DATA_DIR = "./data";
 const DEFAULT_INTERVAL = "30s";
 const DEFAULT_TIMEOUT = "10s";
 const DEFAULT_MAX_CONCURRENT_CHECKS = 20;
+const DEFAULT_RETENTION = "7d";
 
 export interface ResolvedConfig {
   configDir: string;
@@ -22,6 +23,7 @@ export interface ResolvedConfig {
   host: string;
   maxConcurrentChecks: number;
   port: number;
+  retentionMs: number;
   targets: ResolvedTargetBase[];
 }
 
@@ -68,6 +70,7 @@ export async function loadConfig(configPath: string): Promise<ResolvedConfig> {
   const dataDir = server.dataDir ?? DEFAULT_DATA_DIR;
 
   const maxConcurrentChecks = resolveMaxConcurrentChecks(runtime);
+  const retentionMs = resolveRetention(runtime);
 
   const allRuntimeIssues = [...allIssues];
   if (allRuntimeIssues.length > 0) {
@@ -81,7 +84,7 @@ export async function loadConfig(configPath: string): Promise<ResolvedConfig> {
     resolveTarget(target, defaults, defaultIntervalMs, defaultTimeoutMs, configDir),
   );
 
-  return { configDir, dataDir, host, maxConcurrentChecks, port, targets };
+  return { configDir, dataDir, host, maxConcurrentChecks, port, retentionMs, targets };
 }
 
 function canRunSemanticValidation(value: unknown): boolean {
@@ -117,6 +120,10 @@ function resolveMaxConcurrentChecks(runtime: EngineRuntimeConfig): number {
   return runtime.maxConcurrentChecks;
 }
 
+function resolveRetention(runtime: EngineRuntimeConfig): number {
+  return parseDuration(runtime.retention ?? DEFAULT_RETENTION);
+}
+
 function resolveTarget(
   target: RawTargetConfig,
   defaults: DefaultsConfig,
@@ -194,6 +201,11 @@ function validateConfig(config: RawProbeConfig): ConfigValidationIssue[] {
 
   validateDurationValue(config.defaults?.interval, "defaults.interval", issues);
   validateDurationValue(config.defaults?.timeout, "defaults.timeout", issues);
+  validateDurationValue(
+    typeof config.runtime?.retention === "string" ? config.runtime.retention : undefined,
+    "runtime.retention",
+    issues,
+  );
   for (let i = 0; i < config.targets.length; i++) {
     const target = config.targets[i] as unknown;
     if (!isRecord(target)) continue;