Reflects the switch from hard-coded FRONTEND_BASE_URL/utils.deep_links to
admin-managed NotificationLink rows: implementation.md documents the
resolution logic and the new migration, frontend-notification-click-actions.md
replaces the "confirm your URL scheme" ask with the actual code catalog
(now that the scheme itself is an admin panel concern, not something the
frontend team needs to weigh in on for us to ship), and
notification-click-actions.md gets a pointer at the top so it reads as the
historical first pass it now is, not the current mechanism.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>