feat: implement schema manager base functionality

apps/schema-manager/src/__tests__/application.spec.ts

+import type { INestApplication } from '@nestjs/common';
+
+import { Test } from '@nestjs/testing';
+
+import { Application } from '../application.js';
+
+describe('Application', () => {
+  let app: INestApplication;
+
+  beforeAll(async () => {
+    const moduleFixture = await Test.createTestingModule({
+      imports: [Application],
+    }).compile();
+
+    app = moduleFixture.createNestApplication();
+    await app.init();
+  });
+
+  afterAll(async () => {
+    await app.close();
+  });
+
+  it('should be defined', () => {
+    expect(app).toBeDefined();
+  });
+});