feat(cli): add managed service lifecycle

Co-Authored-By: Paperclip <noreply@paperclip.ing>

server/src/index.ts

@@ -72,6 +72,7 @@ import { maybePersistWorktreeRuntimePorts } from "./worktree-config.js";
 import { initTelemetry, getTelemetryClient } from "./telemetry.js";
 import { conflict } from "./errors.js";
 import { coordinateHeartbeatSchedulerShutdown } from "./shutdown.js";
+import { systemdNotify } from "./services/systemd-notify.js";
 import type {
   InstanceDatabaseBackupRunResult,
   InstanceDatabaseBackupTrigger,
@@ -1215,6 +1216,9 @@ export async function startServer(): Promise<StartedServer> {
     server.listen(listenPort, config.host, () => {
       server.off("error", onError);
       logger.info(`Server listening on ${config.host}:${listenPort}`);
+      void systemdNotify(["--ready", `--status=Listening on ${config.host}:${listenPort}`]).then((notified) => {
+        if (notified) logger.info("Notified systemd that Paperclip is ready");
+      });
       if (process.env.PAPERCLIP_OPEN_ON_LISTEN === "true") {
         const openHost = config.host === "0.0.0.0" || config.host === "::" ? "127.0.0.1" : config.host;
         const url = `http://${openHost}:${listenPort}`;
@@ -1268,6 +1272,7 @@ export async function startServer(): Promise<StartedServer> {
   
   {
     const shutdown = async (signal: "SIGINT" | "SIGTERM") => {
+      await systemdNotify(["--stopping", `--status=Stopping after ${signal}`]);
       heartbeatSchedulerStopped = true;
       if (heartbeatSchedulerInterval) {
         clearInterval(heartbeatSchedulerInterval);

server/src/services/systemd-notify.ts

@@ -0,0 +1,8 @@
+import { execFile } from "node:child_process";
+
+export async function systemdNotify(args: string[]): Promise<boolean> {
+  if (!process.env.NOTIFY_SOCKET?.trim()) return false;
+  return await new Promise<boolean>((resolve) => {
+    execFile("systemd-notify", args, { windowsHide: true }, (error) => resolve(!error));
+  });
+}