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/dom-accessibility-api/dist/polyfills/array.from.mjs

@@ -0,0 +1,87 @@
+/**
+ * @source {https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/from#Polyfill}
+ * but without thisArg (too hard to type, no need to `this`)
+ */
+var toStr = Object.prototype.toString;
+function isCallable(fn) {
+  return typeof fn === "function" || toStr.call(fn) === "[object Function]";
+}
+function toInteger(value) {
+  var number = Number(value);
+  if (isNaN(number)) {
+    return 0;
+  }
+  if (number === 0 || !isFinite(number)) {
+    return number;
+  }
+  return (number > 0 ? 1 : -1) * Math.floor(Math.abs(number));
+}
+var maxSafeInteger = Math.pow(2, 53) - 1;
+function toLength(value) {
+  var len = toInteger(value);
+  return Math.min(Math.max(len, 0), maxSafeInteger);
+}
+/**
+ * Creates an array from an iterable object.
+ * @param iterable An iterable object to convert to an array.
+ */
+
+/**
+ * Creates an array from an iterable object.
+ * @param iterable An iterable object to convert to an array.
+ * @param mapfn A mapping function to call on every element of the array.
+ * @param thisArg Value of 'this' used to invoke the mapfn.
+ */
+export default function arrayFrom(arrayLike, mapFn) {
+  // 1. Let C be the this value.
+  // edit(@eps1lon): we're not calling it as Array.from
+  var C = Array;
+
+  // 2. Let items be ToObject(arrayLike).
+  var items = Object(arrayLike);
+
+  // 3. ReturnIfAbrupt(items).
+  if (arrayLike == null) {
+    throw new TypeError("Array.from requires an array-like object - not null or undefined");
+  }
+
+  // 4. If mapfn is undefined, then let mapping be false.
+  // const mapFn = arguments.length > 1 ? arguments[1] : void undefined;
+
+  if (typeof mapFn !== "undefined") {
+    // 5. else
+    // 5. a If IsCallable(mapfn) is false, throw a TypeError exception.
+    if (!isCallable(mapFn)) {
+      throw new TypeError("Array.from: when provided, the second argument must be a function");
+    }
+  }
+
+  // 10. Let lenValue be Get(items, "length").
+  // 11. Let len be ToLength(lenValue).
+  var len = toLength(items.length);
+
+  // 13. If IsConstructor(C) is true, then
+  // 13. a. Let A be the result of calling the [[Construct]] internal method
+  // of C with an argument list containing the single item len.
+  // 14. a. Else, Let A be ArrayCreate(len).
+  var A = isCallable(C) ? Object(new C(len)) : new Array(len);
+
+  // 16. Let k be 0.
+  var k = 0;
+  // 17. Repeat, while k < len… (also steps a - h)
+  var kValue;
+  while (k < len) {
+    kValue = items[k];
+    if (mapFn) {
+      A[k] = mapFn(kValue, k);
+    } else {
+      A[k] = kValue;
+    }
+    k += 1;
+  }
+  // 18. Let putStatus be Put(A, "length", len, true).
+  A.length = len;
+  // 20. Return A.
+  return A;
+}
+//# sourceMappingURL=array.from.mjs.map