Consider supporting tracing-subscriber for diagnostics from domain?

[mozzieongit]

The diagnostics provided by domain could help easily debug issues in the future. But this would add another dependency which we might want to avoid considering packaging.

[ximon18]

Looked at more broadly I would say the question is do we want dnst users to be able to see domain tracing based diagnostics (do we even want tracing based diagnostics in domain???) and if so how do we do that, and how should users be expected to enable it (e.g. -vvvv or RUST_LOG=debug or something else)?