rust/bt-ascs: Add debug command-line tool for client

Add a new debug tool to interactively test and debug the ASCS client
implementation. This provides a convenient way to manually trigger all
client-side operations and inspect the state of remote ASEs.

 - Implement a command-line interface in `src/debug.rs`.
 - Provide commands for all client operations (e.g., `config-codec`,
   `enable`, `release`).
 - Add unit tests for the new argument parsing logic.

Bug: 431814103
Test: cargo test -p bt-ascs
Change-Id: I3f0dd46b2d668545c4f216e0c156c4f4507d4db6
Reviewed-on: https://bluetooth-review.googlesource.com/c/bluetooth/+/2520