Improve verification response

[binbin-li]

What would you like to be added?

Referring to the current verification response: https://ratify.dev/docs/next/reference/verification-result-version#100, there are a few areas we could improve to be more descriptive and informative.

1. Besides message field un verifierReport, we need another field(reason, error details or other names) to carry the root cause of an error if the verification fails. And the message should just report an overall result of the verification.
2. Refine the field names of verifierReports, like the name and type. Probably we should rename to verifierName and verifierType to minimize confusion.
3. (Might out of scope) configPolicy and regoPolicy make decisions in terms of different versions of verifierReports. As v1.0.0 provides more information than v0.1.0, we could consider migrating configPolicy to evaluate on v1.0.0 reports as well. But this might involves a lot of refactoring on config policy evaluation process.

Anything else you would like to add?

No response

Are you willing to submit PRs to contribute to this feature?

• [ ] Yes, I am willing to implement it.