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/istanbul-reports/lib/lcovonly/index.js

@@ -0,0 +1,77 @@
+/*
+ Copyright 2012-2015, Yahoo Inc.
+ Copyrights licensed under the New BSD License. See the accompanying LICENSE file for terms.
+ */
+'use strict';
+const { ReportBase } = require('istanbul-lib-report');
+
+class LcovOnlyReport extends ReportBase {
+    constructor(opts) {
+        super();
+        opts = opts || {};
+        this.file = opts.file || 'lcov.info';
+        this.projectRoot = opts.projectRoot || process.cwd();
+        this.contentWriter = null;
+    }
+
+    onStart(root, context) {
+        this.contentWriter = context.writer.writeFile(this.file);
+    }
+
+    onDetail(node) {
+        const fc = node.getFileCoverage();
+        const writer = this.contentWriter;
+        const functions = fc.f;
+        const functionMap = fc.fnMap;
+        const lines = fc.getLineCoverage();
+        const branches = fc.b;
+        const branchMap = fc.branchMap;
+        const summary = node.getCoverageSummary();
+        const path = require('path');
+
+        writer.println('TN:');
+        const fileName = path.relative(this.projectRoot, fc.path);
+        writer.println('SF:' + fileName);
+
+        Object.values(functionMap).forEach(meta => {
+            // Some versions of the instrumenter in the wild populate 'loc'
+            // but not 'decl':
+            const decl = meta.decl || meta.loc;
+            writer.println('FN:' + [decl.start.line, meta.name].join(','));
+        });
+        writer.println('FNF:' + summary.functions.total);
+        writer.println('FNH:' + summary.functions.covered);
+
+        Object.entries(functionMap).forEach(([key, meta]) => {
+            const stats = functions[key];
+            writer.println('FNDA:' + [stats, meta.name].join(','));
+        });
+
+        Object.entries(lines).forEach(entry => {
+            writer.println('DA:' + entry.join(','));
+        });
+        writer.println('LF:' + summary.lines.total);
+        writer.println('LH:' + summary.lines.covered);
+
+        Object.entries(branches).forEach(([key, branchArray]) => {
+            const meta = branchMap[key];
+            if (meta) {
+                const { line } = meta.loc.start;
+                branchArray.forEach((b, i) => {
+                    writer.println('BRDA:' + [line, key, i, b].join(','));
+                });
+            } else {
+                console.warn('Missing coverage entries in', fileName, key);
+            }
+        });
+        writer.println('BRF:' + summary.branches.total);
+        writer.println('BRH:' + summary.branches.covered);
+        writer.println('end_of_record');
+    }
+
+    onEnd() {
+        this.contentWriter.close();
+    }
+}
+
+module.exports = LcovOnlyReport;