Address PR #227 re-review (comment 2193).
- Stability: `updatePageId`/`updateAlias` now `executeTakeFirstOrThrow`, so a row
reaped by a concurrent `removeAlias` between the read and the UPDATE (READ
COMMITTED) raises `NoResultError` instead of returning `undefined`. The service
maps that to a retryable `ConflictException` (`ALIAS_PAGE_RACE`) rather than a
200-without-alias (swap) or a generic 400 from `undefined.id` (rename). Tests
cover both branches.
- Simplification: drop the redundant secondary "unexpected unique index" warn and
the now-unused `UNIQUE_ALIAS_INDEX` const (the constraint name is already logged
unconditionally; both index branches still distinguish "Alias already taken" vs
ALIAS_PAGE_RACE).
- Architecture: extract `isUniqueViolation`/`violatedConstraint` into
database/utils.ts; adopt them in the share-alias service and favorite.repo
(the bare `23505` check). ai-agent-roles (#222) is on a separate unmerged branch
and should adopt them after #227 merges (noted at the helpers). Helper unit test
added.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>