Add Playwright E2E testing setup

- Added Playwright configuration for automated and visual E2E tests
- Updated Next.js configuration to accept localhost:3003 for testing
- Included Playwright as a dev dependency

💘 Generated with Crush
Co-Authored-By: Crush <crush@charm.land>

tests/example.spec.ts

@@ -0,0 +1,6 @@
+import { test, expect } from '@playwright/test';
+
+test('basic test', async ({ page }) => {
+  await page.goto('http://localhost:3002'); // replace with your local dev URL
+  await expect(page).toHaveTitle(/Spliit · Share Expenses with Friends & Family/); // replace with your app's title
+});