Lucas BergerandClaude Sonnet 4.6
72977334fc
Wrap the last-admin check and UPDATE in a db.transaction with a
SELECT...FOR UPDATE locking read so concurrent PATCH demotions
serialise and cannot both pass the guard, eliminating the TOCTOU
race (CR-01).
Add a .refine() to updateMemberSchema requiring at least one field,
returning 400 via noEchoHook instead of crashing Drizzle with an
empty SET clause (WR-06).
Add Test H asserting empty {} -> 400 { error: 'Invalid request' }.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>