Refactor API and enhance Angular integration

- Removed `ciTargetName` from `nx.json`.
- Updated `package.json` to include new dependencies: `@types/seedrandom`, `fast-check`, `happy-dom`, and `@nestjs/schedule`.
- Modified `pnpm-lock.yaml` to reflect the addition of new packages and their versions.
- Improved project documentation in `PROJECT_CONTEXT.md` to clarify the use of Zod schemas and Angular framework decisions.
- Introduced new Angular components and patterns in the `.agents/skills/frontend-angular` directory, including examples and reference materials for Angular 21+ features.

apps/overlay/src/app/ebs/ebs-api.service.spec.ts

@@ -0,0 +1,78 @@
+import { provideHttpClient } from '@angular/common/http';
+import {
+  HttpTestingController,
+  provideHttpClientTesting,
+} from '@angular/common/http/testing';
+import { TestBed } from '@angular/core/testing';
+import { EbsApiService, EBS_BASE_URL } from './ebs-api.service';
+
+const BASE = 'https://test.local';
+
+describe('EbsApiService', () => {
+  let service: EbsApiService;
+  let controller: HttpTestingController;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [
+        provideHttpClient(),
+        provideHttpClientTesting(),
+        { provide: EBS_BASE_URL, useValue: BASE },
+      ],
+    });
+    service = TestBed.inject(EbsApiService);
+    controller = TestBed.inject(HttpTestingController);
+  });
+
+  afterEach(() => controller.verify());
+
+  describe('getMissionState', () => {
+    it('GETs /missions/state and returns null for no active mission', () => {
+      let result: unknown;
+      service.getMissionState().subscribe((v) => (result = v));
+
+      controller.expectOne(`${BASE}/missions/state`).flush(null);
+      expect(result).toBeNull();
+    });
+
+    it('throws ZodError when server returns invalid shape', () => {
+      let error: unknown;
+      service.getMissionState().subscribe({ error: (e) => (error = e) });
+
+      controller.expectOne(`${BASE}/missions/state`).flush({ bad: 'data' });
+      expect(error).toBeDefined();
+    });
+  });
+
+  describe('startMission', () => {
+    it('POSTs to /missions/start with difficulty', () => {
+      service.startMission({ difficulty: 2 }).subscribe({ error: () => undefined });
+
+      const req = controller.expectOne(`${BASE}/missions/start`);
+      expect(req.request.method).toBe('POST');
+      expect(req.request.body).toEqual({ difficulty: 2 });
+      req.flush({ bad: 'shape' });
+    });
+
+    it('throws ZodError for invalid difficulty before sending request', () => {
+      expect(() => service.startMission({ difficulty: 99 })).toThrow();
+      controller.expectNone(`${BASE}/missions/start`);
+    });
+  });
+
+  describe('choosePerk', () => {
+    it('POSTs to /missions/choose-perk with perkKey', () => {
+      service.choosePerk({ perkKey: 'iron_will' }).subscribe({ error: () => undefined });
+
+      const req = controller.expectOne(`${BASE}/missions/choose-perk`);
+      expect(req.request.method).toBe('POST');
+      expect(req.request.body).toEqual({ perkKey: 'iron_will' });
+      req.flush({ bad: 'shape' });
+    });
+
+    it('throws ZodError for empty perkKey before sending request', () => {
+      expect(() => service.choosePerk({ perkKey: '' })).toThrow();
+      controller.expectNone(`${BASE}/missions/choose-perk`);
+    });
+  });
+});