Documentation of ouraTypes could use some help

[emiflake]

From what I have found, the clearest documentation for the types oura emits through the various pub-sub streams is in ouraTypes.ts. And this serves quite well for reading through the core types. But there are two notable issues:

• It's hard to find this file anywhere, I happened across it while browsing this repo.
• GenericJson isn't generic at all. It follows a specific format that is unspecified anywhere but clearly has its roots in the pallas source code with specific decisions made. A user of oura will have to manually reverse how it's implemented and follow the breadcrumbs back to the rust source code. Of course, it differs between plutus_data and script_json, but they both follow specific formats.

I propose we give a little bit more attention to this file, or create a proper document for it, either works. Then, I propose we drop GenericJson in favour of more specific types that actually follow the implementation in oura, and ultimately in pallas. I suppose for the latter bit, if pallas itself had documentation for these types, we could instead link there, but I have not found anything there either.