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/@testing-library/user-event/dist/esm/utils/focus/cursor.js

@@ -0,0 +1,124 @@
+import { isContentEditable } from '../edit/isContentEditable.js';
+import { isElementType } from '../misc/isElementType.js';
+
+function getNextCursorPosition(node, offset, direction, inputType) {
+    // The behavior at text node zero offset is inconsistent.
+    // When walking backwards:
+    // Firefox always moves to zero offset and jumps over last offset.
+    // Chrome jumps over zero offset per default but over last offset when Shift is pressed.
+    // The cursor always moves to zero offset if the focus area (contenteditable or body) ends there.
+    // When walking forward both ignore zero offset.
+    // When walking over input elements the cursor moves before or after that element.
+    // When walking over line breaks the cursor moves inside any following text node.
+    if (isTextNode(node) && offset + direction >= 0 && offset + direction <= node.nodeValue.length) {
+        return {
+            node,
+            offset: offset + direction
+        };
+    }
+    const nextNode = getNextCharacterContentNode(node, offset, direction);
+    if (nextNode) {
+        if (isTextNode(nextNode)) {
+            return {
+                node: nextNode,
+                offset: direction > 0 ? Math.min(1, nextNode.nodeValue.length) : Math.max(nextNode.nodeValue.length - 1, 0)
+            };
+        } else if (isElementType(nextNode, 'br')) {
+            const nextPlusOne = getNextCharacterContentNode(nextNode, undefined, direction);
+            if (!nextPlusOne) {
+                // The behavior when there is no possible cursor position beyond the line break is inconsistent.
+                // In Chrome outside of contenteditable moving before a leading line break is possible.
+                // A leading line break can still be removed per deleteContentBackward.
+                // A trailing line break on the other hand is not removed by deleteContentForward.
+                if (direction < 0 && inputType === 'deleteContentBackward') {
+                    return {
+                        node: nextNode.parentNode,
+                        offset: getOffset(nextNode)
+                    };
+                }
+                return undefined;
+            } else if (isTextNode(nextPlusOne)) {
+                return {
+                    node: nextPlusOne,
+                    offset: direction > 0 ? 0 : nextPlusOne.nodeValue.length
+                };
+            } else if (direction < 0 && isElementType(nextPlusOne, 'br')) {
+                return {
+                    node: nextNode.parentNode,
+                    offset: getOffset(nextNode)
+                };
+            } else {
+                return {
+                    node: nextPlusOne.parentNode,
+                    offset: getOffset(nextPlusOne) + (direction > 0 ? 0 : 1)
+                };
+            }
+        } else {
+            return {
+                node: nextNode.parentNode,
+                offset: getOffset(nextNode) + (direction > 0 ? 1 : 0)
+            };
+        }
+    }
+}
+function getNextCharacterContentNode(node, offset, direction) {
+    const nextOffset = Number(offset) + (direction < 0 ? -1 : 0);
+    if (offset !== undefined && isElement(node) && nextOffset >= 0 && nextOffset < node.children.length) {
+        node = node.children[nextOffset];
+    }
+    return walkNodes(node, direction === 1 ? 'next' : 'previous', isTreatedAsCharacterContent);
+}
+function isTreatedAsCharacterContent(node) {
+    if (isTextNode(node)) {
+        return true;
+    }
+    if (isElement(node)) {
+        if (isElementType(node, [
+            'input',
+            'textarea'
+        ])) {
+            return node.type !== 'hidden';
+        } else if (isElementType(node, 'br')) {
+            return true;
+        }
+    }
+    return false;
+}
+function getOffset(node) {
+    let i = 0;
+    while(node.previousSibling){
+        i++;
+        node = node.previousSibling;
+    }
+    return i;
+}
+function isElement(node) {
+    return node.nodeType === 1;
+}
+function isTextNode(node) {
+    return node.nodeType === 3;
+}
+function walkNodes(node, direction, callback) {
+    for(;;){
+        var _node_ownerDocument;
+        const sibling = node[`${direction}Sibling`];
+        if (sibling) {
+            node = getDescendant(sibling, direction === 'next' ? 'first' : 'last');
+            if (callback(node)) {
+                return node;
+            }
+        } else if (node.parentNode && (!isElement(node.parentNode) || !isContentEditable(node.parentNode) && node.parentNode !== ((_node_ownerDocument = node.ownerDocument) === null || _node_ownerDocument === undefined ? undefined : _node_ownerDocument.body))) {
+            node = node.parentNode;
+        } else {
+            break;
+        }
+    }
+}
+function getDescendant(node, direction) {
+    while(node.hasChildNodes()){
+        node = node[`${direction}Child`];
+    }
+    return node;
+}
+
+export { getNextCursorPosition };

frontend/node_modules/@testing-library/user-event/dist/esm/utils/focus/getActiveElement.js

@@ -0,0 +1,20 @@
+import { isDisabled } from '../misc/isDisabled.js';
+
+function getActiveElement(document) {
+    const activeElement = document.activeElement;
+    if (activeElement === null || activeElement === undefined ? undefined : activeElement.shadowRoot) {
+        return getActiveElement(activeElement.shadowRoot);
+    } else {
+        // Browser does not yield disabled elements as document.activeElement - jsdom does
+        if (isDisabled(activeElement)) {
+            return document.ownerDocument ? /* istanbul ignore next */ document.ownerDocument.body : document.body;
+        }
+        return activeElement;
+    }
+}
+function getActiveElementOrBody(document) {
+    var _getActiveElement;
+    return (_getActiveElement = getActiveElement(document)) !== null && _getActiveElement !== undefined ? _getActiveElement : /* istanbul ignore next */ document.body;
+}
+
+export { getActiveElement, getActiveElementOrBody };

frontend/node_modules/@testing-library/user-event/dist/esm/utils/focus/getTabDestination.js

@@ -0,0 +1,78 @@
+import { isDisabled } from '../misc/isDisabled.js';
+import { isElementType } from '../misc/isElementType.js';
+import { isVisible } from '../misc/isVisible.js';
+import { FOCUSABLE_SELECTOR } from './selector.js';
+
+function getTabDestination(activeElement, shift) {
+    const document = activeElement.ownerDocument;
+    const focusableElements = document.querySelectorAll(FOCUSABLE_SELECTOR);
+    const enabledElements = Array.from(focusableElements).filter((el)=>el === activeElement || !(Number(el.getAttribute('tabindex')) < 0 || isDisabled(el)));
+    // tabindex has no effect if the active element has negative tabindex
+    if (Number(activeElement.getAttribute('tabindex')) >= 0) {
+        enabledElements.sort((a, b)=>{
+            const i = Number(a.getAttribute('tabindex'));
+            const j = Number(b.getAttribute('tabindex'));
+            if (i === j) {
+                return 0;
+            } else if (i === 0) {
+                return 1;
+            } else if (j === 0) {
+                return -1;
+            }
+            return i - j;
+        });
+    }
+    const checkedRadio = {};
+    let prunedElements = [
+        document.body
+    ];
+    const activeRadioGroup = isElementType(activeElement, 'input', {
+        type: 'radio'
+    }) ? activeElement.name : undefined;
+    enabledElements.forEach((currentElement)=>{
+        const el = currentElement;
+        // For radio groups keep only the active radio
+        // If there is no active radio, keep only the checked radio
+        // If there is no checked radio, treat like everything else
+        if (isElementType(el, 'input', {
+            type: 'radio'
+        }) && el.name) {
+            // If the active element is part of the group, add only that
+            if (el === activeElement) {
+                prunedElements.push(el);
+                return;
+            } else if (el.name === activeRadioGroup) {
+                return;
+            }
+            // If we stumble upon a checked radio, remove the others
+            if (el.checked) {
+                prunedElements = prunedElements.filter((e)=>!isElementType(e, 'input', {
+                        type: 'radio',
+                        name: el.name
+                    }));
+                prunedElements.push(el);
+                checkedRadio[el.name] = el;
+                return;
+            }
+            // If we already found the checked one, skip
+            if (typeof checkedRadio[el.name] !== 'undefined') {
+                return;
+            }
+        }
+        prunedElements.push(el);
+    });
+    for(let index = prunedElements.findIndex((el)=>el === activeElement);;){
+        index += shift ? -1 : 1;
+        // loop at overflow
+        if (index === prunedElements.length) {
+            index = 0;
+        } else if (index === -1) {
+            index = prunedElements.length - 1;
+        }
+        if (prunedElements[index] === activeElement || prunedElements[index] === document.body || isVisible(prunedElements[index])) {
+            return prunedElements[index];
+        }
+    }
+}
+
+export { getTabDestination };

frontend/node_modules/@testing-library/user-event/dist/esm/utils/focus/isFocusable.js

@@ -0,0 +1,7 @@
+import { FOCUSABLE_SELECTOR } from './selector.js';
+
+function isFocusable(element) {
+    return element.matches(FOCUSABLE_SELECTOR);
+}
+
+export { isFocusable };

frontend/node_modules/@testing-library/user-event/dist/esm/utils/focus/selection.js

@@ -0,0 +1,17 @@
+import { isClickableInput } from '../click/isClickableInput.js';
+import { isEditableInputOrTextArea } from '../edit/isEditable.js';
+
+/**
+ * Determine if the element has its own selection implementation
+ * and does not interact with the Document Selection API.
+ */ function hasOwnSelection(node) {
+    return isElement(node) && isEditableInputOrTextArea(node);
+}
+function hasNoSelection(node) {
+    return isElement(node) && isClickableInput(node);
+}
+function isElement(node) {
+    return node.nodeType === 1;
+}
+
+export { hasNoSelection, hasOwnSelection };

frontend/node_modules/@testing-library/user-event/dist/esm/utils/focus/selector.js

@@ -0,0 +1,12 @@
+const FOCUSABLE_SELECTOR = [
+    'input:not([type=hidden]):not([disabled])',
+    'button:not([disabled])',
+    'select:not([disabled])',
+    'textarea:not([disabled])',
+    '[contenteditable=""]',
+    '[contenteditable="true"]',
+    'a[href]',
+    '[tabindex]:not([disabled])'
+].join(', ');
+
+export { FOCUSABLE_SELECTOR };