test(api): общий хелпер с фиксированным RSA-ключом

Фиксированный ключ (OIDC_RSA_PRIVATE_KEY) вместо generateKeyPair
на каждое построение приложения: фаза тестов 9.9с → 1.6с (×6).
Локальные копии buildTestApp/adminToken в 4 файлах заменены на helpers.ts

apps/api/test/app-switcher.test.ts

@@ -1,17 +1,9 @@
 import { describe, expect, it } from 'vitest'
-import { buildApp } from '../src/app.js'
-import { loadConfig } from '../src/config.js'
+import { buildTestApp } from './helpers.js'
 
 describe('app-switcher API', () => {
   it('GET /api/v1/app-switcher is public and returns defaults', async () => {
-    const config = loadConfig({
-      ...process.env,
-      JWT_SECRET: 'test-secret-at-least-8',
-      ADMIN_PASSWORD: 'admin',
-      DATABASE_URL: 'sqlite::memory:',
-      NODE_ENV: 'test',
-    })
-    const app = await buildApp({ config, databaseUrl: 'sqlite::memory:' })
+    const app = await buildTestApp()
     const res = await app.inject({ method: 'GET', url: '/api/v1/app-switcher' })
     expect(res.statusCode).toBe(200)
     const body = res.json() as { menuLabel: string; apps: { id: string }[] }
@@ -38,15 +30,7 @@ describe('app-switcher API', () => {
   })
 
   it('PUT /api/v1/admin/app-switcher requires admin and persists', async () => {
-    const config = loadConfig({
-      ...process.env,
-      JWT_SECRET: 'test-secret-at-least-8',
-      ADMIN_EMAIL: '[email protected]',
-      ADMIN_PASSWORD: 'adminpass',
-      DATABASE_URL: 'sqlite::memory:',
-      NODE_ENV: 'test',
-    })
-    const app = await buildApp({ config, databaseUrl: 'sqlite::memory:' })
+    const app = await buildTestApp()
 
     const denied = await app.inject({
       method: 'PUT',