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/utils/camelize.js

@@ -0,0 +1,37 @@
+"use strict";
+
+const { asciiLowercase } = require("./strings");
+
+// Utility to translate from `border-width` to `borderWidth`.
+// NOTE: For values prefixed with webkit, e.g. `-webkit-foo`, we need to provide
+// both `webkitFoo` and `WebkitFoo`. Here we only return `webkitFoo`.
+exports.dashedToCamelCase = function (dashed) {
+  if (dashed.startsWith("--")) {
+    return dashed;
+  }
+  let camel = "";
+  let nextCap = false;
+  // skip leading hyphen in vendor prefixed value, e.g. -webkit-foo
+  let i = /^-webkit-/.test(dashed) ? 1 : 0;
+  for (; i < dashed.length; i++) {
+    if (dashed[i] !== "-") {
+      camel += nextCap ? dashed[i].toUpperCase() : dashed[i];
+      nextCap = false;
+    } else {
+      nextCap = true;
+    }
+  }
+  return camel;
+};
+
+// Utility to translate from `borderWidth` to `border-width`.
+exports.camelCaseToDashed = function (camelCase) {
+  if (camelCase.startsWith("--")) {
+    return camelCase;
+  }
+  const dashed = asciiLowercase(camelCase.replace(/(?<=[a-z])[A-Z]/g, "-$&"));
+  if (/^webkit-/.test(dashed)) {
+    return `-${dashed}`;
+  }
+  return dashed;
+};

frontend/node_modules/cssstyle/lib/utils/propertyDescriptors.js

@@ -0,0 +1,16 @@
+"use strict";
+
+const prepareValue = require("../parsers").prepareValue;
+
+module.exports.getPropertyDescriptor = function getPropertyDescriptor(property) {
+  return {
+    set(v) {
+      this._setProperty(property, prepareValue(v));
+    },
+    get() {
+      return this.getPropertyValue(property);
+    },
+    enumerable: true,
+    configurable: true
+  };
+};

frontend/node_modules/cssstyle/lib/utils/strings.js

@@ -0,0 +1,167 @@
+// Forked from https://github.com/jsdom/jsdom/blob/main/lib/jsdom/living/helpers/strings.js
+
+"use strict";
+
+// https://infra.spec.whatwg.org/#ascii-whitespace
+const asciiWhitespaceRe = /^[\t\n\f\r ]$/;
+exports.asciiWhitespaceRe = asciiWhitespaceRe;
+
+// https://infra.spec.whatwg.org/#ascii-lowercase
+exports.asciiLowercase = (s) => {
+  const len = s.length;
+  const out = new Array(len);
+  for (let i = 0; i < len; i++) {
+    const code = s.charCodeAt(i);
+    // If the character is between 'A' (65) and 'Z' (90), convert using bitwise OR with 32
+    out[i] = code >= 65 && code <= 90 ? String.fromCharCode(code | 32) : s[i];
+  }
+  return out.join("");
+};
+
+// https://infra.spec.whatwg.org/#ascii-uppercase
+exports.asciiUppercase = (s) => {
+  const len = s.length;
+  const out = new Array(len);
+  for (let i = 0; i < len; i++) {
+    const code = s.charCodeAt(i);
+    // If the character is between 'a' (97) and 'z' (122), convert using bitwise AND with ~32
+    out[i] = code >= 97 && code <= 122 ? String.fromCharCode(code & ~32) : s[i];
+  }
+  return out.join("");
+};
+
+// https://infra.spec.whatwg.org/#strip-newlines
+exports.stripNewlines = (s) => {
+  return s.replace(/[\n\r]+/g, "");
+};
+
+// https://infra.spec.whatwg.org/#strip-leading-and-trailing-ascii-whitespace
+exports.stripLeadingAndTrailingASCIIWhitespace = (s) => {
+  return s.replace(/^[ \t\n\f\r]+/, "").replace(/[ \t\n\f\r]+$/, "");
+};
+
+// https://infra.spec.whatwg.org/#strip-and-collapse-ascii-whitespace
+exports.stripAndCollapseASCIIWhitespace = (s) => {
+  return s
+    .replace(/[ \t\n\f\r]+/g, " ")
+    .replace(/^[ \t\n\f\r]+/, "")
+    .replace(/[ \t\n\f\r]+$/, "");
+};
+
+// https://html.spec.whatwg.org/multipage/infrastructure.html#valid-simple-colour
+exports.isValidSimpleColor = (s) => {
+  return /^#[a-fA-F\d]{6}$/.test(s);
+};
+
+// https://infra.spec.whatwg.org/#ascii-case-insensitive
+exports.asciiCaseInsensitiveMatch = (a, b) => {
+  if (a.length !== b.length) {
+    return false;
+  }
+
+  for (let i = 0; i < a.length; ++i) {
+    if ((a.charCodeAt(i) | 32) !== (b.charCodeAt(i) | 32)) {
+      return false;
+    }
+  }
+
+  return true;
+};
+
+// https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#rules-for-parsing-integers
+// Error is represented as null.
+const parseInteger = (exports.parseInteger = (input) => {
+  // The implementation here is slightly different from the spec's. We want to use parseInt(), but parseInt() trims
+  // Unicode whitespace in addition to just ASCII ones, so we make sure that the trimmed prefix contains only ASCII
+  // whitespace ourselves.
+  const numWhitespace = input.length - input.trimStart().length;
+  if (/[^\t\n\f\r ]/.test(input.slice(0, numWhitespace))) {
+    return null;
+  }
+  // We don't allow hexadecimal numbers here.
+  // eslint-disable-next-line radix
+  const value = parseInt(input, 10);
+  if (Number.isNaN(value)) {
+    return null;
+  }
+  // parseInt() returns -0 for "-0". Normalize that here.
+  return value === 0 ? 0 : value;
+});
+
+// https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#rules-for-parsing-non-negative-integers
+// Error is represented as null.
+exports.parseNonNegativeInteger = (input) => {
+  const value = parseInteger(input);
+  if (value === null) {
+    return null;
+  }
+  if (value < 0) {
+    return null;
+  }
+  return value;
+};
+
+// https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-floating-point-number
+const floatingPointNumRe = /^-?(?:\d+|\d*\.\d+)(?:[eE][-+]?\d+)?$/;
+exports.isValidFloatingPointNumber = (str) => floatingPointNumRe.test(str);
+
+// https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#rules-for-parsing-floating-point-number-values
+// Error is represented as null.
+exports.parseFloatingPointNumber = (str) => {
+  // The implementation here is slightly different from the spec's. We need to use parseFloat() in order to retain
+  // accuracy, but parseFloat() trims Unicode whitespace in addition to just ASCII ones, so we make sure that the
+  // trimmed prefix contains only ASCII whitespace ourselves.
+  const numWhitespace = str.length - str.trimStart().length;
+  if (/[^\t\n\f\r ]/.test(str.slice(0, numWhitespace))) {
+    return null;
+  }
+  const parsed = parseFloat(str);
+  return isFinite(parsed) ? parsed : null;
+};
+
+// https://infra.spec.whatwg.org/#split-on-ascii-whitespace
+exports.splitOnASCIIWhitespace = (str) => {
+  let position = 0;
+  const tokens = [];
+  while (position < str.length && asciiWhitespaceRe.test(str[position])) {
+    position++;
+  }
+  if (position === str.length) {
+    return tokens;
+  }
+  while (position < str.length) {
+    const start = position;
+    while (position < str.length && !asciiWhitespaceRe.test(str[position])) {
+      position++;
+    }
+    tokens.push(str.slice(start, position));
+    while (position < str.length && asciiWhitespaceRe.test(str[position])) {
+      position++;
+    }
+  }
+  return tokens;
+};
+
+// https://infra.spec.whatwg.org/#split-on-commas
+exports.splitOnCommas = (str) => {
+  let position = 0;
+  const tokens = [];
+  while (position < str.length) {
+    let start = position;
+    while (position < str.length && str[position] !== ",") {
+      position++;
+    }
+    let end = position;
+    while (start < str.length && asciiWhitespaceRe.test(str[start])) {
+      start++;
+    }
+    while (end > start && asciiWhitespaceRe.test(str[end - 1])) {
+      end--;
+    }
+    tokens.push(str.slice(start, end));
+    if (position < str.length) {
+      position++;
+    }
+  }
+  return tokens;
+};