Lanes delete into the trash — storage, loader, writer, and undo

Phase 1 of the lanes-in-trash card (2026-07-29 ruling, docs led the
code): lane delete is a move into .trash/ with the subtree intact,
arriving at top trash rank — no destructive delete remains outside
the trash.

TrashedLane opaque unit (id/schema/title/order/heldCards) beside
trash cards — deliberately not a Lane, so no card-shaped surface can
believe an empty subtree. Loader's trash walk trusts the kind VALUE
(lane → opaque unit w/ held-card count counted at the loader's own
unit; card → ordinary card; absent/unrecognized → UUID-children
shape, empty-kindless falls to card per 01's honest limit). Writer:
moveIntoTrash generalized with kind passed never derived (an empty
lane would re-derive as card), deleteLaneToTrash mints against the
whole-container rank ladder. Retired: migrateTombstonedLane (lane
deleted: now ignored — loads live, bytes inert, tolerate-tier
warning), removeLane, captureSubtree/recreateSubtree and the
subtree-snapshot machinery. Undo inverse = move back to captured
strip position, redo replays at captured trash rank. Purge walks
lane subtrees; TrashModel.Freight phrases confirms with lane freight
("…and its 5 cards"). ItemPath gains .trashLane; resolve interleaves
the trash by rank; SearchFilter matches lane rows by title only.
Trashed-lane card windows dismiss and pending cuts void via the
ordinary vanish rule — no new plumbing.

Phase 2 (rendering, selection grammar, drag, a11y, agent guide)
follows. Both schemes 1858 tests / 318 suites green.

Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY

Kanban/UI/Board/TrashCommands.swift

@@ -35,7 +35,7 @@ final class TrashConfirmations {
         /// reachable inside the trash now: the trash's own staged Delete, and Empty Trash (which names
         /// the whole container and re-derives its targets at the moment it runs).
         enum Action: Equatable {
-            case deleteTrashCards(Set<ItemID>)
+            case deleteTrashEntries(Set<ItemID>)
             case emptyTrash
         }
     }
@@ -43,8 +43,8 @@ final class TrashConfirmations {
     /// **File ▸ Delete, staged by place** (04-interactions.md ▸ The map) — with the confirmation the
     /// trash side owes and the board side does not.
     ///
-    /// A board selection goes straight through: moving a card into the trash and deleting a lane are
-    /// both recoverable (the trash itself, and native undo — 03-board-ui.md § Trash), so neither
+    /// A board selection goes straight through: a card and a lane alike move into the trash, and the
+    /// move is recoverable (the trash itself, and native undo — 03-board-ui.md § Trash), so neither
     /// stands an alert. A **trash** selection is the permanent one, and it "confirms exactly where
     /// the loss is real": `purgeIsUnrecoverable` decides.
     ///
@@ -71,7 +71,7 @@ final class TrashConfirmations {
     /// is what a board that keeps history does for every permanent delete (delete-never-forgets).
     func requestTrashDelete(of ids: Set<ItemID>, in store: BoardStore) {
         guard store.purgeIsUnrecoverable else {
-            store.deleteTrashCards(ids)
+            store.deleteTrashEntries(ids)
             return
         }
         guard let prompt = TrashModel.purgePrompt(
@@ -79,7 +79,7 @@ final class TrashConfirmations {
             snapshot: store.snapshot,
             unrecoverable: true
         ) else { return }
-        pending = Pending(prompt: prompt, action: .deleteTrashCards(ids))
+        pending = Pending(prompt: prompt, action: .deleteTrashEntries(ids))
     }
 
     /// Raises Empty Trash…'s alert. **Always** — it guards bulk scope rather than per-item
@@ -98,7 +98,7 @@ final class TrashConfirmations {
         guard let pending else { return }
         self.pending = nil
         switch pending.action {
-        case let .deleteTrashCards(ids): store.deleteTrashCards(ids)
+        case let .deleteTrashEntries(ids): store.deleteTrashEntries(ids)
         case .emptyTrash: store.emptyTrash()
         }
     }
@@ -168,9 +168,10 @@ struct TrashCommands: View {
 extension BoardStore {
 
     /// **Trash shown and non-empty** (11-command-nexus.md's own scope for the Empty Trash… row) —
-    /// where "non-empty" reads `.trash/` itself and never the filtered view (03-board-ui.md § Trash:
-    /// "menu validation's non-empty reads `.trash/`, not the filtered view", so a search that hides
-    /// every trash card leaves the command enabled and its confirmation still names the true count).
+    /// where "non-empty" reads `.trash/` itself — **both kinds of entry**, and never the filtered
+    /// view (03-board-ui.md § Trash: "menu validation's non-empty reads `.trash/`, not the filtered
+    /// view", so a search that hides every trash row leaves the command enabled and its confirmation
+    /// still names the true count, lane freight included).
     ///
     /// The visibility clause is 04-interactions.md's, stated for the whole column: "hidden, it is
     /// invisible to every gesture".
@@ -179,7 +180,7 @@ extension BoardStore {
     /// menu (`TrashModel`'s own reason for being a pure function of a snapshot).
     var canEmptyTrash: Bool {
         guard acceptsBoardMutations, transient.isTrashVisible else { return false }
-        return !snapshot.trash.isEmpty
+        return !snapshot.trash.isEmpty || !snapshot.trashedLanes.isEmpty
     }
 }