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

KanbanTests/EchoLedgerTests.swift

@@ -271,7 +271,7 @@ struct EchoLedgerWriterTests {
         let from = fixture.url("\(lane1)/\(card1)")
 
         try EchoLedger.$current.withValue(ledger) {
-            _ = try BoardWriter.deleteCardToTrash(at: from, inBoard: fixture.root, order: 1024)
+            _ = try BoardWriter.deleteCardToTrash(at: from, inBoard: fixture.root)
         }
 
         let to = fixture.url(".trash/\(card1)")
@@ -594,13 +594,11 @@ struct EchoLedgerHealMarkTests {
         try EchoLedger.$current.withValue(ledger) {
             _ = try BoardWriter.migrateTombstonedCard(
                 at: fixture.url("\(lane1)/\(Ident.card3)"),
-                inBoard: fixture.root,
-                order: 1024
+                inBoard: fixture.root
             )
             _ = try BoardWriter.deleteCardToTrash(
                 at: fixture.url("\(lane1)/\(card1)"),
-                inBoard: fixture.root,
-                order: 2048
+                inBoard: fixture.root
             )
         }