feat(api): add better-auth admin plugin + close public sign-up (migration 0002)

apps/api/test/schema.test.ts

@@ -2,9 +2,7 @@ import { describe, it, expect } from 'vitest';
 import { eq } from 'drizzle-orm';
 import { db } from '../src/db/client';
 import { activities, workSessions, user } from '../src/db/schema';
-import { createApp } from '../src/app';
-
-const json = { 'content-type': 'application/json' };
+import { createTestUser } from './helpers';
 
 describe('domain schema', () => {
   it('creates and reads back an activity with a json insole_types array', async () => {
@@ -20,19 +18,10 @@ describe('domain schema', () => {
   });
 
   it('defaults a work_sessions row to status=active, source=app, pair_count=2, null end_time', async () => {
-    const app = createApp();
-    const creds = {
-      email: 'schema-user@example.com',
-      password: 'sterk-wachtwoord-123',
-      name: 'Schema User',
-    };
-    await app.request('/api/auth/sign-up/email', {
-      method: 'POST',
-      headers: json,
-      body: JSON.stringify(creds),
-    });
+    const email = 'schema-user@example.com';
+    await createTestUser(email);
 
-    const [createdUser] = await db.select().from(user).where(eq(user.email, creds.email));
+    const [createdUser] = await db.select().from(user).where(eq(user.email, email));
     expect(createdUser).toBeTruthy();
 
     const [activity] = await db