feat(analytics): enhanced dashboard analytics and CSV/PDF reporting

[Flamki]

Closes #211

Summary

Implements Enhanced Dashboard Analytics & Reporting with SQL-backed aggregation and export support.

What was added

Backend analytics module

• Added GET /analytics/report
  • summary metrics (total tx, successful tx, failed tx, conversion rate)
  • total volume (USD equivalent)
  • average transaction size
  • asset distribution
  • time-series
• Added GET /analytics/time-series
  • supports daily, weekly, monthly
• Added GET /analytics/assets
  • asset distribution breakdown
• Added GET /analytics/export
  • supports csv and pdf
  • supports report presets: accounting and tax

SQL aggregation (complex DB-side queries)

• Added Supabase migration:
  • app/backend/supabase/migrations/20260429010000_create_analytics_rpc_functions.sql
• Functions:
  • quickex_analytics_summary
  • quickex_analytics_asset_distribution
  • quickex_analytics_time_series
• Backend uses these RPC functions first, with service-level fallback when RPCs are unavailable.

Frontend integration

• Replaced mock analytics fetching with live backend integration.
• Added export actions in analytics dashboard:
  • Export CSV
  • Export PDF
  • Report type selector (accounting / tax)

Validation

• Backend lint: pass
• Backend tests (analytics unit): pass
• Backend build: pass
• Frontend lint: pass
• Frontend build: pass

Notes for reviewers

• Please apply the new Supabase migration before testing analytics endpoints.

[drips-wave]

@Flamki Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits