fix: 安全性与代码质量加固（异常保护、外键级联、竞态修复、优雅关机）

src/server/dev.ts

@@ -14,6 +14,14 @@ async function main() {
   const engine = new ProbeEngine(store, config.targets, config.maxConcurrentChecks);
   engine.start();
 
+  const shutdown = () => {
+    engine.stop();
+    store.close();
+    process.exit(0);
+  };
+  process.on("SIGINT", shutdown);
+  process.on("SIGTERM", shutdown);
+
   startServer({
     config: { host: config.host, port: config.port },
     mode: "development",