Feature/analytics intelligence engine

[Ritesh2332]

Summary

This PR introduces a live engagement analytics tracking system for public profile and card views.

The implementation adds a centralized analytics event architecture using Prisma models and reusable tracking services while preserving backward compatibility with the existing CardView tracking system.

The new analytics layer enables scalable event-driven tracking for future analytics dashboards, engagement insights, and conversion funnel features.

Closes #

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Type of Change

• Bug fix
• New feature
• Refactor (no functional change)
• UI / Design change
• Tests only
• Documentation
• Infrastructure / DevOps
• Security

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What Changed

• Added new EngagementEvent analytics model to Prisma schema
• Added analytics database migration for engagement event storage
• Added centralized trackEvent() analytics service
• Added privacy-safe IP hashing using SHA-256
• Added typed analytics event architecture with reusable event types
• Integrated live analytics tracking into public profile routes
• Integrated live analytics tracking into public card routes
• Preserved backward compatibility with existing CardView tracking system
• Added structured metadata support for future analytics expansion

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How to Test

1. Start services:

docker compose up -d

2. Run backend:

pnpm dev

3. Open a public profile route:

http://127.0.0.1:3000/api/u/<username>

4. Verify analytics events are stored:

SELECT event_type, source, metadata
FROM engagement_events;

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Checklist

• My code follows the project's coding style
• TypeScript compiles for the added analytics layer
• No debug statements or console logs were left in the code
• Existing functionality remains backward compatible
• Database migrations were successfully applied

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Additional Context

This PR lays the foundation for future analytics features such as:

• profile engagement dashboards
• card performance tracking
• QR analytics
• traffic aggregation
• conversion funnels
• unique visitor insights