- Export COLOR_PALETTE (6 accessible hex hues, round-robin assignment) - upsertUser(oidcIss, oidcSub, displayName?) keyed on iss+sub never email - First login: COUNT existing users → assign COLOR_PALETTE[count % len] - Re-upsert: returns existing row unchanged (idempotent, no duplicate insert) - Uses $returningId() + re-select pattern (mysql2 no RETURNING clause) - All 6 tests pass (GREEN)