Build coach team-readiness dashboard with global metrics and athlete score table

[Copilot]

Implemented the main supervisor/coach dashboard to surface team readiness at a glance: a responsive global metrics view and an athlete-level readiness table with threshold-based severity cues. The UI now works even before backend integration by falling back to mock readiness data.

• Dashboard scope rewritten to team readiness

  • Replaced the previous mixed map/chat/route layout in Dashboard.jsx with a coach-focused readiness dashboard.
  • Added a responsive top metrics grid for:
    • Team Average Score (circular indicator)
    • Critical Alerts (count of athletes with score < 50%)

• Athlete readiness table

  • Added a clean data table of athletes with latest calculated score.
  • Applied required score bands:
    • Green: > 80%
    • Orange: 50–80%
    • Red: < 50%

• Data integration + fallback behavior

  • Added polling for GET /team-readiness.
  • Added normalization/guardrails for incoming athlete records and scores.
  • If API data is unavailable/invalid, the dashboard falls back to local mock athletes to keep the UI functional.

• Operational and accessibility refinements

  • Extracted score thresholds and conversion constants to avoid duplicated magic values.
  • Made polling interval configurable via env (VITE_TEAM_READINESS_POLL_MS).
  • Added proper progress semantics (role="progressbar" with ARIA values) and keyboard-visible row focus states.

const criticalAlerts = athletes.filter((a) => a.latestScore < CRITICAL_THRESHOLD).length;
const teamAverageScore = athletes.length
  ? Math.round(athletes.reduce((sum, a) => sum + a.latestScore, 0) / athletes.length)
  : 0;