/admin/reset and reset_environment.reset() act on os.environ['SUPABASE_URL'].
A platform-admin call on a prod-deployed API would wipe prod data + exam
corpus + storage. Refuse when the target matches a known prod marker
(.156 / supabase.classroomcopilot) unless RESET_ALLOW_PROD=1 is set.
Addresses overwatch review finding #1 on feature/exam-seeding-overhaul.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>