feat: built-in test dashboard (/dashboard)

[Kwickos]

A zero-build static dashboard to test everything the API does — and what's coming next.

Added

• web/index.html — single-file dashboard (vanilla JS, no dependencies), served by FastAPI at /dashboard (+ / redirect):
  • Overview — live counts (leagues, matches, in-progress, upcoming) from real ingested data
  • Leagues — ingested leagues with logos
  • Matches — paginated table with status filter; click a row → game inspector
  • Game inspector — event timeline (KILL/TOWER/DRAGON/BARON/INHIB badges) + gold-diff sparkline + latest frame
  • Live console — WebSocket client for /live/{game_id} streaming event/score messages
  • Request log — every API call with status + latency
  • Roadmap panel — done/next/later, so future phases (API keys…) have a visible home
• Tests: dashboard served + root redirect.

Verified

• ruff clean · pytest 16/16
• Real run against the live server: / → 307 → /dashboard/, JS syntax-checked (node), real WebSocket ack end-to-end, real data (80 matches / 8 leagues) rendered.