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/patchFocus.js

@@ -0,0 +1,104 @@
+'use strict';
+
+var dispatchEvent = require('../event/dispatchEvent.js');
+require('../utils/dataTransfer/Clipboard.js');
+var getActiveElement = require('../utils/focus/getActiveElement.js');
+require('@testing-library/dom');
+
+const patched = Symbol('patched focus/blur methods');
+function patchFocus(HTMLElement) {
+    if (HTMLElement.prototype[patched]) {
+        return;
+    }
+    // eslint-disable-next-line @typescript-eslint/unbound-method
+    const { focus, blur } = HTMLElement.prototype;
+    Object.defineProperties(HTMLElement.prototype, {
+        focus: {
+            configurable: true,
+            get: ()=>patchedFocus
+        },
+        blur: {
+            configurable: true,
+            get: ()=>patchedBlur
+        },
+        [patched]: {
+            configurable: true,
+            get: ()=>({
+                    focus,
+                    blur
+                })
+        }
+    });
+    let activeCall;
+    function patchedFocus(options) {
+        if (this.ownerDocument.visibilityState !== 'hidden') {
+            return focus.call(this, options);
+        }
+        const blurred = getActiveTarget(this.ownerDocument);
+        if (blurred === this) {
+            return;
+        }
+        const thisCall = Symbol('focus call');
+        activeCall = thisCall;
+        if (blurred) {
+            blur.call(blurred);
+            dispatchEvent.dispatchDOMEvent(blurred, 'blur', {
+                relatedTarget: this
+            });
+            dispatchEvent.dispatchDOMEvent(blurred, 'focusout', {
+                relatedTarget: activeCall === thisCall ? this : null
+            });
+        }
+        if (activeCall === thisCall) {
+            focus.call(this, options);
+            dispatchEvent.dispatchDOMEvent(this, 'focus', {
+                relatedTarget: blurred
+            });
+        }
+        if (activeCall === thisCall) {
+            dispatchEvent.dispatchDOMEvent(this, 'focusin', {
+                relatedTarget: blurred
+            });
+        }
+    }
+    function patchedBlur() {
+        if (this.ownerDocument.visibilityState !== 'hidden') {
+            return blur.call(this);
+        }
+        const blurred = getActiveTarget(this.ownerDocument);
+        if (blurred !== this) {
+            return;
+        }
+        const thisCall = Symbol('blur call');
+        activeCall = thisCall;
+        blur.call(this);
+        dispatchEvent.dispatchDOMEvent(blurred, 'blur', {
+            relatedTarget: null
+        });
+        dispatchEvent.dispatchDOMEvent(blurred, 'focusout', {
+            relatedTarget: null
+        });
+    }
+}
+function getActiveTarget(document) {
+    const active = getActiveElement.getActiveElement(document);
+    return (active === null || active === undefined ? undefined : active.tagName) === 'BODY' ? null : active;
+}
+function restoreFocus(HTMLElement) {
+    if (HTMLElement.prototype[patched]) {
+        const { focus, blur } = HTMLElement.prototype[patched];
+        Object.defineProperties(HTMLElement.prototype, {
+            focus: {
+                configurable: true,
+                get: ()=>focus
+            },
+            blur: {
+                configurable: true,
+                get: ()=>blur
+            }
+        });
+    }
+}
+
+exports.patchFocus = patchFocus;
+exports.restoreFocus = restoreFocus;