Refactor: regroup "if no mana was spent to cast [target pointer]" in a shared condition

https://scryfall.com/search?q=o%3A%2Fif+no+mana+was+spent%2F&unique=cards&as=grid&order=name

Those cards use various means to look for the "if no mana was spent to cast [target pointer spell]" condition. I think we could make them share some code.

Start with the Scryfall search linked in the issue and inspect the card implementations that check whether no mana was spent to cast a target spell. Identify the differing condition logic and determine whether it can be represented by shared code without changing the affected cards' behavior. Done means the relevant cards use the shared condition consistently.

Written by the indexing model from the issue text.