feat: add a way to internally remove elements

Some client operations (especially inserts) may error in a way that leaves the store in an invalid state, we need client methods to deal with these invalid states before erroring out.

Here's one example of these cases:

> We could have a similar problem here where the `add_account` works but the `add_key` fails (although I think it would be more rare than the previous case)

_Originally posted by @tomyrd in https://github.com/0xMiden/miden-client/pull/899#discussion_r2082543480_