Spin deps CLI

[fibonacci1729]

Implementation of SIP 024.

[itowlson]

This looks good! I struggled with a few things I'm afraid, and I have some naming nits. My main feeling is that I would really like to see the main flows as something like:

fn add_component_dependency() {
  let component_id = select_component();         // }
  let selected_interface = select_interface();   // } as you already have it
  let inheritance = select_inheritance();        // }
  write_dependency_to_manifest();
  regenerate_dependencies_wit();
  print_report();
}

instead if inlining the last half, which for me meant I lost track of what is really a very simple linear flow.

But all that aside the bones seem really solid and it is mostly stylistic confusion on my part. Great to see this under sail!

Addressed

[itowlson]

Couple of wording and erroring suggestions which we can iterate on over time, no blockers.

I admit I found all the Wasm parser stuff a bit hairy but the main UI stuff was a model of clarity, and I really appreciate the work that went into structuring it so cleanly - thank you!