feat: migrate from RapidAPI to TheSportsDB with SvelteKit dashboard
- Replace free-api-live-football-data (RapidAPI) backend with TheSportsDB
- Add PostgreSQL cache layer for permanent data (teams, players, leagues, events)
- Replace Bootstrap dashboard with SvelteKit-based interactive dashboard
- Restructure MCP tools around TheSportsDB capabilities (get_team_info, get_roster, get_fixtures, get_standings, etc.)
- Expose tool registry via GET /api/tools so dashboard stays in sync
- Remove legacy modules and references (api_football, sync, RapidAPI env vars)