Review follow-ups for the Reference lifecycle fix:
- photo.setReference refuses an id that is not a photo id instead of
pinning the active photo; only an absent or null id means the active one.
- A Recently Deleted photo is refused with a message that says to restore
it (setReference and view.reference); the grid menu item is disabled for
it and any refusal is shown as a toast, not dropped.
- Reference view with no live pin releases its panes (windows, region and
pane textures, full capacity) like other views.
- A successful library switch leaves Reference for the grid; the Compare
pair is now cleared only on success, like the reference pin.
- One compare::live helper replaces four copies of the "exists and not
deleted" check.
- whats-new entry moved to 2026-10-21; checklist and ui-parity dates bumped.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
