test: add auth API integration tests

backend/tests/auth.spec.js

@@ -0,0 +1,56 @@
+// Test für Auth-API Endpunkte
+import { test, expect } from '@playwright/test';
+
+test.describe('Auth API Tests', () => {
+  test('should register a new user', async ({ request }) => {
+    const response = await request.post('/auth/register', {
+      data: {
+        email: 'test@example.com',
+        password: 'password123',
+        name: 'Test User'
+      }
+    });
+    
+    expect(response.status()).toBe(201);
+    const responseBody = await response.json();
+    expect(responseBody).toHaveProperty('userId');
+    expect(responseBody).toHaveProperty('email', 'test@example.com');
+  });
+
+  test('should login with valid credentials', async ({ request }) => {
+    const response = await request.post('/auth/login', {
+      data: {
+        email: 'test@example.com',
+        password: 'password123'
+      }
+    });
+    
+    expect(response.status()).toBe(200);
+    const responseBody = await response.json();
+    expect(responseBody).toHaveProperty('token');
+    expect(responseBody).toHaveProperty('userId');
+  });
+
+  test('should not login with invalid credentials', async ({ request }) => {
+    const response = await request.post('/auth/login', {
+      data: {
+        email: 'test@example.com',
+        password: 'wrongpassword'
+      }
+    });
+    
+    expect(response.status()).toBe(401);
+  });
+
+  test('should not register with existing email', async ({ request }) => {
+    const response = await request.post('/auth/register', {
+      data: {
+        email: 'test@example.com',
+        password: 'password123',
+        name: 'Test User'
+      }
+    });
+    
+    expect(response.status()).toBe(409);
+  });
+});