Describe the enhancement

As mentioned in payjoin/rust-payjoin#337, it's way clearer having a Cargo.lock file than having the pinned dependencies only on the README and CI.

In rust-bitcoin it follows a different approach that might be helpful and clearer, opening this issue for start a discussion about it.

Use case

Adds Cargo-minimal.lock and Cargo-recent.lock files for clearer pinned dependencies and MSRV support.

Additional context

Please refer to payjoin/rust-payjoin#337 and rust-bitcoin/rust-bitcoin#1764