Describe the enhancement
I am integrating swift-bdk into Fully Noded (my wallet), it would be very useful to me if swift-bdk exposed the functionality of deriving an address directly from a descriptor. This makes it easy to show the user if any given address belongs to their wallet.

Use case
Fully Noded allows the user to make collaborative transactions and import any transaction, it then parses said transaction to display information to the user about each input and output. Currently I need to initiate a BDKWallet in order to derive addresses and in practice have settled on deriving the extended key only. I see no reason why the underlying Rust functionality can't be exposed in Swift. It would be useful for my wallets purposes and clean up my code quite a bit.

Thank you for the excellent library!