A hull is worth something broken up
Ships can be recycled back into resources, and the yard tells you what you will get before it touches anything.
Every fleet eventually contains hulls nobody flies any more — the scouts you built in week one, the escort pattern you researched past. They sat in the yard because scrapping them returned exactly nothing.
Scrap it back
Ships can now be recycled, and a good part of what they cost comes back. The old tier stops being dead weight and becomes the down payment on the new one.
The screen announces the return before anything is broken up. You see what you will get, and then you decide — a destructive action that makes you guess is a trap, and this one is irreversible.
It is not a full refund, and it should not be: if scrapping returned everything, a fleet would be a savings account with no cost to having built the wrong thing. The rate is a per-galaxy setting, so it is one of the levers a universe can pull to say how forgiving it wants to be.