http-signature-directory validation cli should show step by step validation

At the moment, when the directory validation fail, only the error is displayed.
It could be relevant to show steps that work. For instance

```
Well-known: True
Content-Type: True
JWKS: True

=== For each key
Thumbprint: [computed]
Algorithm: Ed25519
Associated-Signature: True
```

@AkshatM 