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/Storage/BoardModel.swift

@@ -118,16 +118,17 @@ public struct BoardModel: Sendable, Equatable {
     /// **The container's other kind is `trashedLanes`** (re-ruled 2026-07-29 — lanes trash too).
     /// The two are separate arrays rather than one list of a sum type because they are separate
     /// *things*: a trashed card is an ordinary card that every card-shaped surface already reads,
-    /// and a trashed lane is an opaque row that none of them may. Interleaving the two by trash
-    /// rank is a rendering question (03-board-ui.md § Trash: "lane rows and cards interleave in the
-    /// one trash column purely by trash rank"), and both arrays carry the `order` that answers it.
+    /// and a trashed lane is an opaque row that none of them may. Interleaving the two is a
+    /// rendering question (03-board-ui.md § Trash: "lane rows and cards interleave in the one trash
+    /// column by `modified` descending"), and both arrays carry the stamp that answers it —
+    /// `BoardModel.trashEntries` is the one merge.
     ///
-    /// **Display order is `order` ascending, like any lane's cards** — `Ranks.sortedForDisplay`,
-    /// same folder-name tie-break. Newest-first falls out of ordinary ranks rather than a
-    /// timestamp sort: every arrival mints a rank *above* the current topmost
-    /// (`Ranks.insertAtHead`), so the trash needs no sort rule of its own. There is deliberately
-    /// no `deleted:` key on anything in here — a trashed card is an ordinary card in a special
-    /// place.
+    /// **Display order is `modified` descending** — `Ranks.sortedForTrash`, tie-broken by title then
+    /// folder name (re-ruled 2026-07-31, retiring the arrival rank mint). The trash is the one
+    /// container in the app whose sequence is not a rank sequence: the delete move stamps, and that
+    /// stamp *is* the position, with each entry's `order` riding along untouched for its restore.
+    /// There is deliberately no `deleted:` key on anything in here — a trashed card is an ordinary
+    /// card in a special place.
     ///
     /// Empty when `.trash/` is absent (the overwhelmingly common case — the folder is minted by
     /// the first delete), and empty when it holds nothing the loader recognizes as a card.
@@ -281,9 +282,17 @@ public struct TrashedLane: Identifiable, Sendable, Equatable {
     public let schema: Int
     public let title: FieldValue<String>
 
-    /// Rank within the trash, ascending = top to bottom — the same required, strictly validated
-    /// field a live lane carries (`Lane.order`), and what interleaves this row among the trash's
-    /// cards. Newest-first falls out of it: every arrival mints a rank above the current topmost.
+    /// **When the row entered the trash** — and therefore *where it sits*: the trash sorts by
+    /// `modified` descending (01-storage-format.md § Deletion, re-ruled 2026-07-31), and the trash
+    /// move is the container-changing write that stamps it. Missing on a foreign mover that skipped
+    /// the restamp, which sorts it below every dated sibling (`Ranks.isOrderedForTrash`).
+    public let modified: FieldValue<Date>
+
+    /// The lane's rank **among the board's lanes**, riding along untouched — the trash move rewrites
+    /// no `order` at all, so this is still the strip position a restore would want and the value the
+    /// undo of a restore puts back. It is deliberately *not* what orders this row in the column
+    /// (`modified` is), and the same required, strictly validated field a live lane carries
+    /// (`Lane.order`).
     public let order: Double
 
     /// **How many cards the lane is holding** — the row's whole other half ("Doing — 5 cards").