test(web): add Vitest setup and unit tests for validations and utils

- Add vitest config and test script to web app
- Auth validation tests: phone format, password rules, registration flow
- Listing validation tests: all schema steps, constants, merged schema
- Utils tests: cn() class merging with Tailwind conflict resolution
- 36 tests across 3 test files

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/lib/__tests__/auth-validations.spec.ts

@@ -0,0 +1,86 @@
+import { describe, it, expect } from 'vitest';
+import { loginSchema, registerSchema } from '../validations/auth';
+
+describe('loginSchema', () => {
+  it('should accept valid Vietnamese phone and password', () => {
+    const result = loginSchema.safeParse({ phone: '0912345678', password: 'abc123' });
+    expect(result.success).toBe(true);
+  });
+
+  it('should accept +84 format phone', () => {
+    const result = loginSchema.safeParse({ phone: '+84912345678', password: 'abc123' });
+    expect(result.success).toBe(true);
+  });
+
+  it('should reject empty phone', () => {
+    const result = loginSchema.safeParse({ phone: '', password: 'abc123' });
+    expect(result.success).toBe(false);
+  });
+
+  it('should reject invalid phone format', () => {
+    const result = loginSchema.safeParse({ phone: '12345', password: 'abc123' });
+    expect(result.success).toBe(false);
+  });
+
+  it('should reject empty password', () => {
+    const result = loginSchema.safeParse({ phone: '0912345678', password: '' });
+    expect(result.success).toBe(false);
+  });
+
+  it('should accept various valid Vietnamese prefixes', () => {
+    const prefixes = ['032', '056', '070', '081', '090'];
+    for (const prefix of prefixes) {
+      const result = loginSchema.safeParse({ phone: `${prefix}1234567`, password: 'pass' });
+      expect(result.success).toBe(true);
+    }
+  });
+});
+
+describe('registerSchema', () => {
+  const validData = {
+    fullName: 'Nguyen Van A',
+    phone: '0912345678',
+    password: '12345678',
+    confirmPassword: '12345678',
+  };
+
+  it('should accept valid registration data', () => {
+    const result = registerSchema.safeParse(validData);
+    expect(result.success).toBe(true);
+  });
+
+  it('should accept with optional email', () => {
+    const result = registerSchema.safeParse({ ...validData, email: 'test@example.com' });
+    expect(result.success).toBe(true);
+  });
+
+  it('should accept empty string email', () => {
+    const result = registerSchema.safeParse({ ...validData, email: '' });
+    expect(result.success).toBe(true);
+  });
+
+  it('should reject invalid email', () => {
+    const result = registerSchema.safeParse({ ...validData, email: 'not-email' });
+    expect(result.success).toBe(false);
+  });
+
+  it('should reject short password', () => {
+    const result = registerSchema.safeParse({ ...validData, password: '123', confirmPassword: '123' });
+    expect(result.success).toBe(false);
+  });
+
+  it('should reject mismatched passwords', () => {
+    const result = registerSchema.safeParse({ ...validData, confirmPassword: 'different' });
+    expect(result.success).toBe(false);
+  });
+
+  it('should reject short full name', () => {
+    const result = registerSchema.safeParse({ ...validData, fullName: 'A' });
+    expect(result.success).toBe(false);
+  });
+
+  it('should reject empty full name', () => {
+    const result = registerSchema.safeParse({ ...validData, fullName: '' });
+    expect(result.success).toBe(false);
+  });
+});