Build Context-Reattributed RAPM Audit

Project the frozen prior-season HPM context signal onto the realized target season's signed player design, then retain the irreducible lineup-specific remainder as residual synergy:

uv run nba-build-context-reattributed-rapm-audit --through-season 2025-26

The command writes an immutable artifact under artifacts/models/context_reattributed_rapm_audit/2025-26/. It is an interpretability audit, not a new leaderboard candidate: the target season's realized lineups are used to understand an already frozen HPM context state.

The default is 25 possessions, balancing the sparsity of exact ten-player matchups against interpretability. Use --minimum-lineup-possessions 75 to require more evidence before a lineup-pair residual appears in the output table.