[BUG] Undo adds extra step for Dynamic Choice and End Service nodes

[matKlju]

Bug description:
Undoing a Dynamic Choice or End Service node behaves incorrectly: instead of reverting to the original state in a single undo, the undo operation is split into two steps. The first undo shifts the entire node stack to the right, and only the second undo actually removes the node.

Expected behavior:
A single undo action should fully revert the last operation. After adding a Dynamic Choice or End Service node, pressing undo once should both remove the node and restore the original layout without any intermediate state.

Screenshots:
N/A

Additional information:
Repro steps:

1. Add Dynamic Choice or End Service node
2. Press Undo once
   • Result: node stack shifts to the right (unexpected extra undo state)
3. Press Undo again
   • Result: node is removed

Impact:

• Undo history is polluted with a layout-only step
• Causes confusion and breaks expected undo semantics