Redraw a copy's originals at the source — the resting layout follows the operation

The modifier flip (⌥ copy / ⌘ move) now reflows the source board once:
a copy re-admits the dragged originals into the resting layout, standing
dimmed in place, and a move lifts them out as before. This retires
DRAG-REORDER.md's operation-blind carve-out and makes 04-interactions.md's
"originals stay" true in flight, not just at echo. The one seam is
DragSession.hiddenMembers reading the observed operation.

Consequences carried honestly: copyCards now takes its index in the
lane's full rendered space (the zones counted the originals, so the
geometry's number is the writer's number — the old neighbour remap is
deleted); resolveOperation freezes under the committed hold exactly as
propose does, fixing a real bug where a settled within-board ⌥-copy drew
the move arrangement until the echo and visibly re-shuffled. Stationary
flips still wait for the next dropUpdated (their own Backlog card).

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

Kanban/UI/Board/LaneView.swift

@@ -859,11 +859,13 @@ struct LaneView: View {
     /// `lane.cards` and the trash column renders it instead. The tombstone era's ancestor walk and
     /// effective-liveness predicate are retired with the flag they read.
     ///
-    /// **A dragged card renders nowhere either, for as long as the session lasts.** It is lifted out
-    /// of the resting layout at pickup and stays out until release *whatever the effective operation
-    /// is* — a ⌥-copy's originals really do stay, but ⌥ can be pressed and released mid-drag, and a
-    /// layout that re-admitted them on every flip would flap the board under the cursor
-    /// (DRAG-REORDER.md § Resting-layout zones). The copy's originals reappear when the write lands.
+    /// **A card being dragged *as a move* renders nowhere, for as long as the session lasts.** It is
+    /// lifted out of the resting layout at pickup and stays out until release. A card being dragged
+    /// as a **copy** stays exactly where it is and dims (`CardFaceView`), because that is what the
+    /// copy will leave behind — so flipping ⌥ or ⌘ mid-drag reflows this lane once, which is the
+    /// feedback the modifier is asking for (DRAG-REORDER.md § Resting-layout zones, ruled
+    /// 2026-08-01). Either way the drop's index is counted in the layout on screen, which is why
+    /// `copyCards` and `moveCards` take their index in different spaces.
     ///
     /// **A card the live search filter hides renders nowhere either** (04-interactions.md § Search):
     /// "cards whose title *and* body both miss the query animate out". This is the one collection