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/jest-message-util/build/index.d.ts

@@ -0,0 +1,68 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import {StackData} from 'stack-utils';
+import {Config, TestResult} from '@jest/types';
+
+export declare const formatExecError: (
+  error: Error | TestResult.SerializableError | string | number | undefined,
+  config: StackTraceConfig,
+  options: StackTraceOptions,
+  testPath?: string,
+  reuseMessage?: boolean,
+  noTitle?: boolean,
+) => string;
+
+export declare const formatPath: (
+  line: string,
+  config: StackTraceConfig,
+  relativeTestPath?: string | null,
+) => string;
+
+export declare const formatResultsErrors: (
+  testResults: Array<TestResult.AssertionResult>,
+  config: StackTraceConfig,
+  options: StackTraceOptions,
+  testPath?: string,
+) => string | null;
+
+export declare function formatStackTrace(
+  stack: string,
+  config: StackTraceConfig,
+  options: StackTraceOptions,
+  testPath?: string,
+): string;
+
+export declare interface Frame extends StackData {
+  file: string;
+}
+
+export declare function getStackTraceLines(
+  stack: string,
+  options?: StackTraceOptions,
+): Array<string>;
+
+export declare function getTopFrame(lines: Array<string>): Frame | null;
+
+export declare const indentAllLines: (lines: string) => string;
+
+export declare const separateMessageFromStack: (content: string) => {
+  message: string;
+  stack: string;
+};
+
+export declare type StackTraceConfig = Pick<
+  Config.ProjectConfig,
+  'rootDir' | 'testMatch'
+>;
+
+export declare type StackTraceOptions = {
+  noStackTrace: boolean;
+  noCodeFrame?: boolean;
+};
+
+export {};