Feature: Count Deconstruction Entities as negative.
Idea: we can mark some entities with deconstruction planner and replace them with new blueprint. Entities that were marked for deconstruction will be reused.

Example:
Requested = 100 belts (ghosts), marked to deconstruct = 30 belts (red cross). Select both: ghosts and deconstructing entities.
So, in the popup we see — it requires 70 belts ( 100 - 30 = 70 ).

Optional Idea: Count deconstructing entities only with shift+click or right-click for the ghost counter tool in hands.