Graph: expanded transaction node cannot be dragged

[4rkad]

Bug

When a transaction node in the graph explorer is expanded (showing inputs/outputs), it cannot be dragged to reposition it.

Steps to reproduce

1. Open the graph explorer
2. Expand a transaction node (click to show inputs/outputs)
3. Try to drag the node to a new position

Expected behavior

Expanded nodes should be draggable just like collapsed nodes.

Actual behavior

The node is locked in place and cannot be moved while expanded.

[Copexit]

Reopened: the fix for this issue was reverted in commit 3198c04 after review found it wasn't working correctly. Needs a dedicated session.