feat(backend): add /healthz endpoint (#13834)

* feat(backend): add /healthz endpoint

* feat(backend): also check meilisearch status if available

* style: header

* chore: no-store

* chore: healthcheck.sh

* style: format

packages/backend/src/boot/entry.ts

@@ -15,6 +15,7 @@ import Logger from '@/logger.js';
 import { envOption } from '../env.js';
 import { masterMain } from './master.js';
 import { workerMain } from './worker.js';
+import { readyRef } from './ready.js';
 
 import 'reflect-metadata';
 
@@ -79,6 +80,8 @@ if (cluster.isWorker || envOption.disableClustering) {
 	await workerMain();
 }
 
+readyRef.value = true;
+
 // ユニットテスト時にMisskeyが子プロセスで起動された時のため
 // それ以外のときは process.send は使えないので弾く
 if (process.send) {

packages/backend/src/boot/ready.ts

@@ -0,0 +1,6 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export const readyRef = { value: false };