- Add findTeamByNameInSeason (exact case-insensitive match via lower()) to the team model
- Validate uniqueness in the user-facing team settings rename action
- Validate uniqueness in admin assign-owner and remove-owner paths that auto-generate names
- Reject whitespace-only team names that would trim to an empty string
- Add DB-level unique index on (season_id, lower(name)) to close the TOCTOU race
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
