Implement backend API and database services in Docker setup

- Added a new `api` service for the NestJS backend, including health checks and dependencies on PostgreSQL, Redis, and MinIO.
- Introduced PostgreSQL and Redis services with health checks and configurations for data persistence.
- Added MinIO for S3-compatible object storage and a one-shot service to initialize required buckets.
- Updated the Nginx configuration to proxy requests to the new backend API and MinIO storage.
- Enhanced the Dockerfile to support the new API environment variables and configurations.
- Updated the `package.json` and `package-lock.json` to include new dependencies for QR code generation and other utilities.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/test/app.e2e-spec.ts

@@ -0,0 +1,29 @@
+// eslint-disable-next-line unicorn/prevent-abbreviations
+import { Test, TestingModule } from '@nestjs/testing';
+import { INestApplication } from '@nestjs/common';
+import * as request from 'supertest';
+import { AppController } from './../src/app.controller';
+import { AppService } from './../src/app.service';
+
+describe('AppController (e2e)', () => {
+  let app: INestApplication;
+
+  beforeEach(async () => {
+    const moduleFixture: TestingModule = await Test.createTestingModule({
+      controllers: [AppController],
+      providers: [AppService],
+    }).compile();
+
+    app = moduleFixture.createNestApplication();
+    await app.init();
+  });
+
+  it('/ (GET)', () => {
+    return request(app.getHttpServer())
+      .get('/')
+      .expect(200)
+      .expect((response) =>
+        expect(response.text).toMatch(/App has been running for/),
+      );
+  });
+});