Add Errors namespace to the Website

[ricardozanini]

What would you like to be added:
We have errors namespaced by our domain in the new DSL: https://github.com/serverlessworkflow/specification/blob/main/dsl-reference.md#standard-error-types

It would be nice to have them documented (dynamically, by using CI) on the website as well.

Why is this needed:
Users can fetch the error-rich description by accessing the URL when seeing the log in a runtime implementation

[JBBianchi]

Do you want me to take care of it @ricardozanini ?

[ricardozanini]

@JBBianchi oh please! The idea is to have a JSON, TXT, and HTML representation. But for a first iteration, I believe just TXT makes sense now.