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/cssstyle/lib/allExtraProperties.js

@@ -0,0 +1,49 @@
+"use strict";
+
+/**
+ * This file contains all implemented properties that are not a part of any
+ * current specifications or drafts, but are handled by browsers nevertheless.
+ */
+
+const allWebkitProperties = require("./allWebkitProperties");
+
+module.exports = new Set([
+  "background-position-x",
+  "background-position-y",
+  "background-repeat-x",
+  "background-repeat-y",
+  "color-interpolation",
+  "color-profile",
+  "color-rendering",
+  "enable-background",
+  "glyph-orientation-horizontal",
+  "kerning",
+  "marker-offset",
+  "marks",
+  "pointer-events",
+  "shape-rendering",
+  "size",
+  "src",
+  "stop-color",
+  "stop-opacity",
+  "text-anchor",
+  "text-line-through",
+  "text-line-through-color",
+  "text-line-through-mode",
+  "text-line-through-style",
+  "text-line-through-width",
+  "text-overline",
+  "text-overline-color",
+  "text-overline-mode",
+  "text-overline-style",
+  "text-overline-width",
+  "text-rendering",
+  "text-underline",
+  "text-underline-color",
+  "text-underline-mode",
+  "text-underline-style",
+  "text-underline-width",
+  "unicode-range",
+  "vector-effect",
+  ...allWebkitProperties
+]);