A liveness flip is a vanish — selection re-resolves by UUID and liveness side

Resolves the 02-vs-04 contradiction: foreign edits that flip deleted:
on a selected card eject it from the selection (and pending cut, which
already behaved this way), so 04's homogeneous-by-liveness invariant
holds across reloads and menu validation never sees a mixed selection.

Claude-Session: https://claude.ai/code/session_01HJ7PhFNmQ19bvy9RMD6GSb

DESIGN/04-interactions.md

@@ -58,7 +58,7 @@ The trash quasi-lane (03-board-ui.md ▸ Trash) speaks the same keyboard languag
 
 - **Navigation**: the shown trash is the **last container for card navigation** — arrows walk into and out of it, and ⌥→ jumps to it. The quasi-lane itself is never selectable *as a lane* (no lane op applies to it): with a lane selected, ←/→ and ⌥→ stop at the last real lane.
 - **Moves are inert across the boundary**: no move or paste ever targets the trash (deleting is ⌫/⌘⌫), and ⌥⌘↑/⌥⌘↓ are inert *on* tombstoned cards (moving out is Put Back or drag-to-restore).
-- **Selection is homogeneous by liveness** (extending the homogeneous-selection rule): a selection never mixes live and tombstoned cards. Select All selects visible live cards only; a rubber-band stays on the side of the boundary it started on. Menu validation stays binary — Delete for live selections, Put Back / Delete Immediately for tombstoned ones.
+- **Selection is homogeneous by liveness** (extending the homogeneous-selection rule): a selection never mixes live and tombstoned cards. Select All selects visible live cards only; a rubber-band stays on the side of the boundary it started on. Menu validation stays binary — Delete for live selections, Put Back / Delete Immediately for tombstoned ones. External liveness flips can't breach the invariant: a reload that flips `deleted:` on a selected card ejects it from the selection (02-architecture.md's reload-survival rule — a flip is a vanish from its side of the boundary), so validation never sees a mixed selection.
 - **Tombstoned lane entries are full keyboard citizens, homogeneous by kind**: arrows walk every trash entry in its sorted order — card and lane entries alike (a lane's single restorable entry, 03-board-ui.md ▸ Trash) — and the board's cards-XOR-lanes rule extends into the trash: a selection never mixes card entries and lane entries (on top of never mixing live and tombstoned). Put Back (⌘⌫) and Delete Immediately (⌥⌘⌫) apply to lane entries exactly as to cards — a put-back lane returns whole, cards and all. A lane entry is not draggable (its entry is a compact row, not the lane); its copy-out is ⌘C only, and its move-out is Put Back.
 - **Clipboard: copy out only.** ⌘C (cards and lane entries), ⌥-drag, and the cross-board drag default (cards) always yield *live* copies — `deleted:` is stripped on paste/duplicate/drop, like copying a file out of Finder's Trash; a lane entry's copy additionally strips its tombstoned interior cards (the lane-copy rule — copies transfer content, and trash isn't content). ⌘X is disabled: the move-out vocabulary is Put Back or drag-to-restore, nothing else. The *cross-board restore-move* (⌘-drag below) needs no command of its own — its keyboard equivalent is the composition Put Back → ⌘X → ⌘V in the destination: same folder, same identity.
 - **Everything edit-shaped is disabled** on tombstoned selections — Open Card, Rename, Style… (File ▸ Duplicate is untouched: it duplicates the board, never the selection — 11-command-nexus.md; card copies out of the trash are ⌘C or ⌥-drag, which name a live destination). Finder file drops (attachment import) on tombstoned cards are inert — 03-board-ui.md's no-editing-in-the-trash.