Implement analytics and monitoring

[gboigwe]

Description

Add analytics tracking and error monitoring to understand user behavior and catch issues in production.

Requirements

• Event tracking (circle creation, expenses, settlements)
• Error monitoring (Sentry or similar)
• Performance monitoring
• User analytics

Implementation

Analytics Events

• Circle created
• Expense added
• Debt settled
• Wallet connected
• Page views

Error Monitoring

// lib/monitoring.ts
import * as Sentry from '@sentry/nextjs';

Sentry.init({
  dsn: process.env.NEXT_PUBLIC_SENTRY_DSN,
  environment: process.env.NODE_ENV,
});

export function trackEvent(eventName: string, properties?: object) {
  // Analytics implementation
}

export function trackError(error: Error, context?: object) {
  Sentry.captureException(error, { extra: context });
}

Acceptance Criteria

• Analytics tracking implemented
• Error monitoring configured
• Performance metrics tracked
• Privacy-compliant
• Dashboard access configured

Dependencies

• All frontend issues

Estimated Complexity

Medium