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/properties/flex.js

@@ -0,0 +1,73 @@
+"use strict";
+
+const parsers = require("../parsers");
+const flexGrow = require("./flexGrow");
+const flexShrink = require("./flexShrink");
+const flexBasis = require("./flexBasis");
+
+const shorthandFor = new Map([
+  ["flex-grow", flexGrow],
+  ["flex-shrink", flexShrink],
+  ["flex-basis", flexBasis]
+]);
+
+module.exports.parse = function parse(v) {
+  const key = parsers.parseKeyword(v, ["auto", "none"]);
+  if (key) {
+    if (key === "auto") {
+      return "1 1 auto";
+    }
+    if (key === "none") {
+      return "0 0 auto";
+    }
+    if (key === "initial") {
+      return "0 1 auto";
+    }
+    return;
+  }
+  const obj = parsers.parseShorthand(v, shorthandFor);
+  if (obj) {
+    const flex = {
+      "flex-grow": "1",
+      "flex-shrink": "1",
+      "flex-basis": "0%"
+    };
+    const items = Object.entries(obj);
+    for (const [property, value] of items) {
+      flex[property] = value;
+    }
+    return [...Object.values(flex)].join(" ");
+  }
+};
+
+module.exports.isValid = function isValid(v) {
+  if (v === "") {
+    return true;
+  }
+  return typeof module.exports.parse(v) === "string";
+};
+
+module.exports.definition = {
+  set(v) {
+    v = parsers.prepareValue(v, this._global);
+    if (parsers.hasVarFunc(v)) {
+      this._shorthandSetter("flex", "", shorthandFor);
+      this._setProperty("flex", v);
+    } else {
+      this._shorthandSetter("flex", module.exports.parse(v), shorthandFor);
+    }
+  },
+  get() {
+    let val = this.getPropertyValue("flex");
+    if (parsers.hasVarFunc(val)) {
+      return val;
+    }
+    val = this._shorthandGetter("flex", shorthandFor);
+    if (parsers.hasVarFunc(val)) {
+      return "";
+    }
+    return val;
+  },
+  enumerable: true,
+  configurable: true
+};