feat(logging): add comprehensive error boundary and global error handling (Phase 6)

Implemented complete client-side error handling and reporting system:

Error Boundary Component (components/providers/ErrorBoundary.tsx):
- React Error Boundary to catch component errors
- Automatic error logging to client logger
- Error reporting to server endpoint
- User-friendly fallback UI with error details (dev mode)
- Reset and reload functionality
- Custom fallback support via props

Global Error Handler (lib/utils/global-error-handler.ts):
- Window error event listener for uncaught errors
- Unhandled promise rejection handler
- Automatic error reporting to server
- Comprehensive error metadata collection:
  - Error message and stack trace
  - URL, user agent, timestamp
  - Filename, line number, column number (for window errors)

Client Error Reporting Endpoint (app/api/client-error/route.ts):
- Server-side endpoint to receive client errors
- Integrated with withLogging() for automatic server logging
- Accepts error reports from both ErrorBoundary and global handlers
- Returns acknowledgement to client

Error Boundary Integration (components/providers/Providers.tsx):
- Wrapped entire app in ErrorBoundary
- Initialized global error handlers on mount
- Catches React errors, window errors, and unhandled rejections

Error Reporting Features:
- Duplicate error tracking prevention
- Async error reporting (non-blocking)
- Graceful degradation (fails silently if reporting fails)
- Development vs production error display
- Structured error metadata for debugging

All errors now:
- Log to browser console via client logger
- Report to server for centralized logging
- Display user-friendly error UI
- Include full context for debugging
- Work across React, window, and promise contexts

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

lib/utils/global-error-handler.ts

@@ -0,0 +1,108 @@
+'use client';
+
+import { clientLogger } from './client-logger';
+
+/**
+ * Global error handler for unhandled errors and promise rejections
+ * Sets up event listeners for window errors and unhandled promise rejections
+ */
+
+interface ClientErrorReport {
+  message: string;
+  stack?: string;
+  url: string;
+  userAgent: string;
+  timestamp: string;
+  type: 'error' | 'unhandledrejection';
+  filename?: string;
+  lineno?: number;
+  colno?: number;
+}
+
+async function reportErrorToServer(errorReport: ClientErrorReport): Promise<void> {
+  try {
+    await fetch('/api/client-error', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify(errorReport),
+    });
+  } catch (err) {
+    // Silently fail - don't want error reporting to cause more errors
+    console.error('Failed to report error to server:', err);
+  }
+}
+
+/**
+ * Initialize global error handlers
+ * Should be called once when the app starts
+ */
+export function initGlobalErrorHandlers(): void {
+  if (typeof window === 'undefined') {
+    return; // Only run in browser
+  }
+
+  // Handle uncaught errors
+  window.addEventListener('error', (event: ErrorEvent) => {
+    clientLogger.error('Uncaught error', event.error, {
+      message: event.message,
+      filename: event.filename,
+      lineno: event.lineno,
+      colno: event.colno,
+    });
+
+    // Report to server
+    reportErrorToServer({
+      message: event.message,
+      stack: event.error?.stack,
+      url: window.location.href,
+      userAgent: navigator.userAgent,
+      timestamp: new Date().toISOString(),
+      type: 'error',
+      filename: event.filename,
+      lineno: event.lineno,
+      colno: event.colno,
+    }).catch(() => {
+      // Ignore reporting errors
+    });
+  });
+
+  // Handle unhandled promise rejections
+  window.addEventListener('unhandledrejection', (event: PromiseRejectionEvent) => {
+    const reason = event.reason;
+    const message = reason instanceof Error ? reason.message : String(reason);
+    const stack = reason instanceof Error ? reason.stack : undefined;
+
+    clientLogger.error('Unhandled promise rejection', reason, {
+      message,
+      stack,
+    });
+
+    // Report to server
+    reportErrorToServer({
+      message: `Unhandled Promise Rejection: ${message}`,
+      stack,
+      url: window.location.href,
+      userAgent: navigator.userAgent,
+      timestamp: new Date().toISOString(),
+      type: 'unhandledrejection',
+    }).catch(() => {
+      // Ignore reporting errors
+    });
+  });
+
+  clientLogger.info('Global error handlers initialized');
+}
+
+/**
+ * Cleanup global error handlers
+ */
+export function cleanupGlobalErrorHandlers(): void {
+  if (typeof window === 'undefined') {
+    return;
+  }
+
+  // Remove event listeners
+  // Note: We can't remove the exact listeners without keeping references
+  // This is mainly for completeness, in practice these stay for the lifetime of the app
+  clientLogger.info('Global error handlers cleanup requested');
+}