Implement the dashboard page with real data from the API:
- KPI cards (hours, active tasks, total tasks, projects)
- Charts: hours by day (line), hours by project (doughnut),
tasks by status (doughnut), tasks by priority (bar),
tasks by project (horizontal stacked bar)
- Filters: period (week/month), project, user
- Add chart.js and vue-chartjs dependencies
- Add dashboard sidebar icon and translations
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>