Slate v2 liftNodes should compose move, split, and remove to preserve ids

What happened

After exact-path wrapNodes(...) and unwrapNodes(...), the next structural hole was liftNodes(...).

The tempting lie was to rebuild the lifted branch into new wrapper shapes.

That would have made the visible structure look right while quietly replacing the lifted node with a fresh id.

What fixed it

The honest exact-path cut lifts by composing the structural ops that already know how to preserve identity:

1. move the existing node out of its parent
2. split the parent only for the middle-child case
3. remove the emptied parent only for the only-child case

That keeps the lifted node as the same logical node:

• same runtime id
• new sibling path
• surrounding wrappers split or disappear only when structurally necessary

Reusable rule

For Slate v2 structural lift helpers:

• lift by moving the existing node, not by rebuilding it
• split surrounding wrappers only when the lifted node is in the middle
• remove the wrapper only when it becomes empty
• read the live draft tree inside outer transactions

If liftNodes(...) recreates the lifted node, it is not lifting. It is a costume change with identity theft.