Closes#172
- New GET /api/v2/refractor/cards endpoint in refractor router with
team_id (required), card_type, tier, season, progress, limit, offset filters
- season filter uses EXISTS subquery against batting/pitching_season_stats
- progress=close filter uses CASE expression to compare current_value
against next tier threshold (>= 80%)
- LEFT JOIN on Player so deleted players return player_name: null
- Sorting: current_tier DESC, current_value DESC
- count reflects total matching rows before pagination
- Extended _build_card_state_response() with progress_pct (computed) and
optional player_name; single-card endpoint gains progress_pct automatically
- Added non-unique team_id index on refractor_card_state in db_engine.py
- Migration: 2026-03-25_add_refractor_card_state_team_index.sql
- Removed pre-existing unused RefractorTrack import in evaluate_game (ruff)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>