Set up comprehensive frontend testing infrastructure

- Install Jest for unit testing with React Testing Library
- Install Playwright for end-to-end testing
- Configure Jest with proper TypeScript support and module mapping
- Create test setup files and utilities for both unit and e2e tests

Components:
* Jest configuration with coverage thresholds
* Playwright configuration with browser automation
* Unit tests for LoginForm, AuthContext, and useSocketIO hook
* E2E tests for authentication, dashboard, and agents workflows
* GitHub Actions workflow for automated testing
* Mock data and API utilities for consistent testing
* Test documentation with best practices

Testing features:
- Unit tests with 70% coverage threshold
- E2E tests with API mocking and user journey testing
- CI/CD integration for automated test runs
- Cross-browser testing support with Playwright
- Authentication system testing end-to-end

🚀 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/node_modules/@testing-library/user-event/dist/cjs/document/getValueOrTextContent.js

@@ -0,0 +1,18 @@
+'use strict';
+
+require('../utils/dataTransfer/Clipboard.js');
+var isContentEditable = require('../utils/edit/isContentEditable.js');
+var UI = require('./UI.js');
+
+function getValueOrTextContent(element) {
+    // istanbul ignore if
+    if (!element) {
+        return null;
+    }
+    if (isContentEditable.isContentEditable(element)) {
+        return element.textContent;
+    }
+    return UI.getUIValue(element);
+}
+
+exports.getValueOrTextContent = getValueOrTextContent;