Scaffold HIPCTF platform (NestJS + Angular)

- Backend: NestJS 10 + TypeORM (better-sqlite3) feature-modular layout.
  - Entities: user, setting, category, challenge, challenge_file, solve,
    refresh_token, blog_post. Auto-run migrations + idempotent 6-system-
    category seed on startup.
  - Argon2id password hashing with policy check; JWT access + rotating
    refresh tokens (HttpOnly cookie); CSRF middleware (SameSite + custom
    X-CSRF-Token header); global JWT auth guard with @Public() opt-out;
    per-IP login backoff + per-IP registration rate limit.
  - Endpoints: auth (login/refresh/logout/csrf), users (first-admin
    registration), system (bootstrap/event status/SSE), admin (guarded
    user CRUD with last-admin invariant), frontend module (uploads +
    SPA fallback).
  - Security: helmet+CSP+HSTS-gated-by-TLS, CORS allowlist, structured
    global exception filter, Zod request validation pipes, OpenAPI 3.1
    served at /api/docs and /api/docs-json, 10 canonical themes under
    backend/themes/.
- Frontend: Angular 17 standalone components, lazy-loaded feature routes,
  signals, functional HttpInterceptorFn (csrf + auth), functional
  CanActivateFn auth guard, HttpOnly-cookie-based auth service.
- Tests: Jest + supertest, 46 tests across 13 suites covering
  migrations, env schema, theme loader, event status, login backoff,
  registration rate limit, ApiError shape, bootstrap integration,
  auth refresh rotation, admin guard, last-admin invariant, SSE flat
  payloads. Single-command runner: `npm test`.

tests/backend/admin-guard.spec.ts

@@ -0,0 +1,102 @@
+process.env.DATABASE_PATH = ':memory:';
+process.env.THEMES_DIR = './themes';
+process.env.FRONTEND_DIST = './frontend/dist';
+
+import { Test } from '@nestjs/testing';
+import { INestApplication, ValidationPipe } from '@nestjs/common';
+import { HttpAdapterHost } from '@nestjs/core';
+import request from 'supertest';
+import { CookieAccessInfo } from 'cookiejar';
+import cookieParser from 'cookie-parser';
+import { AppModule } from '../../backend/src/app.module';
+import { GlobalExceptionFilter } from '../../backend/src/common/filters/global-exception.filter';
+
+describe('Admin route protection', () => {
+  let app: INestApplication;
+  let adminToken: string;
+
+  beforeAll(async () => {
+    const moduleRef = await Test.createTestingModule({ imports: [AppModule] }).compile();
+    app = moduleRef.createNestApplication();
+    app.use(cookieParser());
+    app.useGlobalPipes(new ValidationPipe({ whitelist: true, forbidNonWhitelisted: false, transform: true }));
+    const httpAdapterHost = app.get(HttpAdapterHost);
+    app.useGlobalFilters(new GlobalExceptionFilter(httpAdapterHost));
+    await app.init();
+
+    const server = app.getHttpServer();
+    await request(server).post('/api/v1/auth/register-first-admin')
+      .send({ username: 'admin', password: 'Sup3rSecret!Pass' })
+      .expect(201);
+
+    const login = await request(server).post('/api/v1/auth/login')
+      .send({ username: 'admin', password: 'Sup3rSecret!Pass' })
+      .expect(201);
+    adminToken = login.body.accessToken;
+  });
+
+  afterAll(async () => {
+    await app.close();
+  });
+
+  it('GET /api/v1/admin/users without a token returns 401', async () => {
+    await request(app.getHttpServer()).get('/api/v1/admin/users').expect(401);
+  });
+
+  it('GET /api/v1/admin/users with a player JWT returns 403', async () => {
+    const server = app.getHttpServer();
+    const agent = request.agent(server);
+
+    // Prime CSRF cookie first.
+    await agent.get('/api/v1/auth/csrf');
+    const cookies: any = agent.jar.getCookies(CookieAccessInfo.All);
+    const csrf = cookies.find((c: any) => c.name === 'csrf');
+
+    // Create a player via admin endpoint
+    await agent.post('/api/v1/admin/users')
+      .set('Authorization', `Bearer ${adminToken}`)
+      .set('X-CSRF-Token', csrf.value)
+      .send({ username: 'player1', password: 'Sup3rSecret!Pass', role: 'player' })
+      .expect(201);
+
+    const playerLogin = await agent.post('/api/v1/auth/login')
+      .set('X-CSRF-Token', csrf.value)
+      .send({ username: 'player1', password: 'Sup3rSecret!Pass' })
+      .expect(201);
+    const playerToken = playerLogin.body.accessToken;
+
+    await request(app.getHttpServer())
+      .get('/api/v1/admin/users')
+      .set('Authorization', `Bearer ${playerToken}`)
+      .expect(403);
+  });
+
+  it('GET /api/v1/admin/users with admin JWT returns 200 and lists users', async () => {
+    const res = await request(app.getHttpServer())
+      .get('/api/v1/admin/users')
+      .set('Authorization', `Bearer ${adminToken}`)
+      .expect(200);
+    expect(Array.isArray(res.body)).toBe(true);
+    expect(res.body.length).toBeGreaterThanOrEqual(2);
+  });
+
+  it('DELETE /api/v1/admin/users/:id on the only admin returns 409 LAST_ADMIN', async () => {
+    const list = await request(app.getHttpServer())
+      .get('/api/v1/admin/users')
+      .set('Authorization', `Bearer ${adminToken}`)
+      .expect(200);
+    const adminRow = list.body.find((u: any) => u.role === 'admin');
+    expect(adminRow).toBeDefined();
+
+    const server = app.getHttpServer();
+    const agent = request.agent(server);
+    await agent.get('/api/v1/auth/csrf');
+    const cookies: any = agent.jar.getCookies(CookieAccessInfo.All);
+    const csrf = cookies.find((c: any) => c.name === 'csrf');
+
+    await agent.delete(`/api/v1/admin/users/${adminRow.id}`)
+      .set('Authorization', `Bearer ${adminToken}`)
+      .set('X-CSRF-Token', csrf.value)
+      .expect(409);
+  });
+});