feat: integrate Playwright for E2E testing and enhance testing framework

- Added Playwright for end-to-end testing in the `apps/web` module, including a new `login.spec.ts` for testing login functionality.
- Updated package.json to include Playwright dependencies and new test commands for E2E testing.
- Enhanced .gitignore to exclude Playwright test results and reports.
- Modified existing documentation to reflect the integration of Playwright and updated testing guidelines.
- Refactored test commands to streamline the testing process, including a dedicated command for E2E tests.

These changes improve the testing framework by providing robust E2E testing capabilities, enhancing the reliability and quality of the application.

apps/web/e2e/fixtures/fake-jwt.ts

@@ -0,0 +1,11 @@
+export function createFakeJwt(expiresInSeconds = 3600): string {
+  const header = Buffer.from(JSON.stringify({ alg: 'none', typ: 'JWT' })).toString('base64url');
+  const payload = Buffer.from(
+    JSON.stringify({
+      sub: 'e2e-user',
+      exp: Math.floor(Date.now() / 1000) + expiresInSeconds,
+    }),
+  ).toString('base64url');
+
+  return `${header}.${payload}.e2e`;
+}