The lane collapse chevron shows a resize cursor on hover — now it shows the standard arrow cursor

Added .onHover modifier to the collapseButton to explicitly set NSCursor.arrow when hovering over the collapse chevron, preventing the lane resize handle's resize cursor from appearing over the button.

Kanban/UI/Board/LaneView.swift

@@ -784,6 +784,9 @@ struct LaneView: View, Equatable {
         .buttonStyle(.plain)
         .accessibilityLabel(AccessibilityPhrases.collapseLaneLabel(lane: lane.title.value))
         .disabled(!store.acceptsBoardMutations)
+        .onHover { inside in
+            if inside { NSCursor.arrow.push() } else { NSCursor.pop() }
+        }
     }
 
     // MARK: - The lane drag