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/react/dist/index.js

@@ -0,0 +1,52 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+var _actCompat = require("./act-compat");
+var _pure = require("./pure");
+Object.keys(_pure).forEach(function (key) {
+  if (key === "default" || key === "__esModule") return;
+  if (key in exports && exports[key] === _pure[key]) return;
+  Object.defineProperty(exports, key, {
+    enumerable: true,
+    get: function () {
+      return _pure[key];
+    }
+  });
+});
+// if we're running in a test runner that supports afterEach
+// or teardown then we'll automatically run cleanup afterEach test
+// this ensures that tests run in isolation from each other
+// if you don't like this then either import the `pure` module
+// or set the RTL_SKIP_AUTO_CLEANUP env variable to 'true'.
+if (typeof process === 'undefined' || !process.env?.RTL_SKIP_AUTO_CLEANUP) {
+  // ignore teardown() in code coverage because Jest does not support it
+  /* istanbul ignore else */
+  if (typeof afterEach === 'function') {
+    afterEach(() => {
+      (0, _pure.cleanup)();
+    });
+  } else if (typeof teardown === 'function') {
+    // Block is guarded by `typeof` check.
+    // eslint does not support `typeof` guards.
+    // eslint-disable-next-line no-undef
+    teardown(() => {
+      (0, _pure.cleanup)();
+    });
+  }
+
+  // No test setup with other test runners available
+  /* istanbul ignore else */
+  if (typeof beforeAll === 'function' && typeof afterAll === 'function') {
+    // This matches the behavior of React < 18.
+    let previousIsReactActEnvironment = (0, _actCompat.getIsReactActEnvironment)();
+    beforeAll(() => {
+      previousIsReactActEnvironment = (0, _actCompat.getIsReactActEnvironment)();
+      (0, _actCompat.setReactActEnvironment)(true);
+    });
+    afterAll(() => {
+      (0, _actCompat.setReactActEnvironment)(previousIsReactActEnvironment);
+    });
+  }
+}