feat: add contacts phase 2, advanced search, vacation responder, Docker & TOTP 2FA

- Contact groups/lists, vCard import/export (RFC 6350), bulk operations
- Advanced search with JMAP filter panel, search chips, cross-mailbox queries
- Vacation responder with JMAP VacationResponse, settings tab, sidebar indicator
- TOTP two-factor authentication support
- Docker multi-stage build with standalone output and docker-compose
- CSP Report-Only headers and security headers via proxy middleware
- Virtual scrolling for large email lists
- Structured server-side logger (text/JSON, configurable level)
- 450+ tests (contacts, vCard, threads, headers, identity, components)
- Playwright E2E framework setup
- Updated README and ROADMAP with all new features

e2e/contacts.spec.ts

@@ -0,0 +1,17 @@
+import { test, expect } from '@playwright/test';
+
+test.describe('Contacts', () => {
+  test.skip('navigates to contacts page', async ({ page }) => {
+    await page.goto('/en/contacts');
+    await expect(page.locator('text=title')).toBeVisible();
+  });
+
+  test.skip('creates a new contact', async ({ page }) => {
+    await page.goto('/en/contacts');
+    await page.click('text=create_new');
+    await page.fill('input[placeholder="given_name"]', 'Test');
+    await page.fill('input[placeholder="surname"]', 'User');
+    await page.fill('input[type="email"]', 'test@example.com');
+    await page.click('button[type="submit"]');
+  });
+});