Realign code with the 2026-07-31 rulings

The trash sorts by modified descending — the arrival rank mint retires
(Ranks.isOrderedForTrash one comparator, loader + merged order agree;
the legacy deleted: migration stamps modified from the tombstone
timestamp where parseable; delete undo steps validate existence-only;
agent guide v8). Trash selection goes kind-blind — ranges, marquee,
Select All, and the successor walk sweep both kinds; the guard moves to
the exits (mixed-payload drop refusal, copy/cut validation). The copy
stamping preflight widens back to comment depth (load-scoped posture —
the board always loads, the gesture refuses whole). Fixes a latent
no-op: trashed-lane drag restore never fired (DragSession.beginLanes
hard-coded the board container).

2403 tests in 413 suites green.

Claude-Session: https://claude.ai/code/session_01CqjXB7ASoWtbyoGod68k97

Kanban/UI/Board/TrashLaneRowView.swift

@@ -183,6 +183,11 @@ struct TrashLaneRowView: View {
     /// **Multi-drag carries the whole trash-side lane selection**, in the column's own order, and a
     /// row outside the selection drags alone — the card face's targeting rule at the other level.
     ///
+    /// **A kind-blind selection can span both kinds, and the session says so** (04-interactions.md ▸
+    /// The trash, ruled 2026-07-31): a `.lanes` session cannot carry the cards in it, so rather than
+    /// drop them silently the flag travels and the release refuses with the notice
+    /// (`DragSession.mixesKinds`) — "pickup is allowed — the selection is legal".
+    ///
     /// Refused under the read-only lock and while an inline editor is focused, like every other
     /// mutating gesture; a refusal is an item provider carrying nothing, so no session begins.
     private func startDrag() -> NSItemProvider {
@@ -190,6 +195,8 @@ struct TrashLaneRowView: View {
         let ids = draggedIDs
         let rows = store.snapshot.trashedLanes.filter { ids.contains($0.id) }
         guard !rows.isEmpty else { return NSItemProvider() }
+        let mixesKinds = SelectionGrammar.mixesKinds(
+            ItemReferenceSet(ids: ids, container: .trash), in: store.snapshot)
 
         let root = store.rootURL
         let payload = DragPayload(
@@ -212,7 +219,12 @@ struct TrashLaneRowView: View {
             // standard width; the restored lane then draws at whatever `width` its untouched
             // frontmatter still says, on the next reload.
             units: rows.map { _ in 1 },
-            source: store
+            // **The session's container is this row's**, matching the payload's — which is what
+            // routes the release to `BoardStore.restoreLanes` (the move *out* of `.trash/`) rather
+            // than to `moveLanes`' strip permutation, and what the mixed-payload exit keys on.
+            container: .trash,
+            source: store,
+            mixesKinds: mixesKinds
         )
         return payload.itemProvider()
     }