* Improve net worth chart
* feat: Add current net worth display to dashboard chart
* Handle different currencies
* Add account balance sync service and update SyncProvider
* Remove redundant transaction filters in DashboardAnalyticsController
- Create DashboardAnalyticsController with 6 analytics endpoints:
- Net worth calculation and comparison
- Monthly spending with period comparison
- Cash flow (income vs expenses)
- Net worth evolution over time
- Account balance history
- Top spending categories
- Add PeriodComparator service for date range comparisons
- Update DashboardController to pass categories, accounts, and banks
- Add comprehensive feature tests for all analytics endpoints
- Register analytics routes under /api/dashboard
Víctor Falcón