chore: import DH V2 D5.6.4 production baseline

api-v3/src/health.service.ts

@@ -0,0 +1,24 @@
+import { Injectable } from '@nestjs/common';
+import { DataSource } from 'typeorm';
+import { API_PHASE, API_VERSION } from './version';
+
+@Injectable()
+export class HealthService {
+  constructor(private readonly dataSource: DataSource) {}
+
+  async check() {
+    const startedAt = Date.now();
+    await this.dataSource.query('SELECT 1');
+
+    return {
+      status: 'ok',
+      service: 'dhv2-api',
+      api: 'v3',
+      version: API_VERSION,
+      phase: API_PHASE,
+      database: 'ok',
+      time: new Date().toISOString(),
+      latencyMs: Date.now() - startedAt,
+    };
+  }
+}