test(waas-engine): add vitest suite and node ssr container adapter setup

tests/waasEngine.test.ts

@@ -0,0 +1,53 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import fs from 'fs';
+import path from 'path';
+import { loadWaasConfigs, FALLBACK_SITE_CONFIG, FALLBACK_THEME_CONFIG, FALLBACK_SMTP_CONFIG } from '../src/utils/configLoader';
+import { THEME_PRESETS } from '../src/utils/themePresets';
+
+describe('WaaS Engine Core Unit Tests', () => {
+  const testDataDir = path.join(process.cwd(), 'app', 'test_data');
+
+  beforeEach(() => {
+    process.env.DATA_DIR = testDataDir;
+    if (fs.existsSync(testDataDir)) {
+      fs.rmSync(testDataDir, { recursive: true, force: true });
+    }
+  });
+
+  afterEach(() => {
+    if (fs.existsSync(testDataDir)) {
+      fs.rmSync(testDataDir, { recursive: true, force: true });
+    }
+  });
+
+  it('1. Should return fallbacks when JSON files do not exist (Zero-Crash Guarantee)', () => {
+    const configs = loadWaasConfigs();
+    expect(configs.siteConfig.siteName).toBe(FALLBACK_SITE_CONFIG.siteName);
+    expect(configs.themeConfig.activePreset).toBe(FALLBACK_THEME_CONFIG.activePreset);
+    expect(configs.smtpConfig.host).toBe(FALLBACK_SMTP_CONFIG.host);
+  });
+
+  it('2. Should dynamically merge custom site.config.json', () => {
+    fs.mkdirSync(testDataDir, { recursive: true });
+    const customSite = { siteName: 'Custom Test Agency', hero: { title: 'Custom Title' } };
+    fs.writeFileSync(path.join(testDataDir, 'site.config.json'), JSON.stringify(customSite), 'utf8');
+
+    const configs = loadWaasConfigs();
+    expect(configs.siteConfig.siteName).toBe('Custom Test Agency');
+    expect(configs.siteConfig.hero.title).toBe('Custom Title');
+    expect(configs.siteConfig.hero.badge).toBe(FALLBACK_SITE_CONFIG.hero.badge);
+  });
+
+  it('3. Should have 10 valid Theme Presets with root CSS color tokens', () => {
+    const presetKeys = Object.keys(THEME_PRESETS);
+    expect(presetKeys.length).toBe(10);
+    expect(THEME_PRESETS.corporateDark.colors.bg).toBe('#0B0F19');
+    expect(THEME_PRESETS.corporateDark.colors.accent).toBe('#38BDF8');
+  });
+
+  it('4. Should support dynamic UIComponent elements in SectionConfig', () => {
+    const heroElements = FALLBACK_SITE_CONFIG.hero.elements || [];
+    expect(heroElements.length).toBeGreaterThan(0);
+    expect(heroElements[0].type).toBe('badge');
+  });
+});