Admin Sports Schedule

Thin wrapper around _admin_sports_schedule_impl so a crash between the fetch and the final render is still visible (Phase 0 perf-plan hardening — see the sports-schedule-explorer-perf-plan canvas). The real handler's own admin.sports_schedule.{fetch,enrich,total} logs only fire on the happy path; reindenting that whole ~250-line body under a try/finally to close that gap directly was judged too risky, so the guarantee lives here instead, one call frame up, where it can't perturb the existing logic at all.

Phase 1: view / tz_offset default to None (param absent) so a cookie can supply the viewer's last preference before any DB/API work.