Protobuf documentation generator

[jjohannes]

Problem

There is a custom documentation generator for protobufs here:
https://github.com/hashgraph/hedera-protobufs-java/tree/main/docgenerator

That repository is on the way to get archived. The primary location for the "Hedera" protobufs is now:
https://github.com/hiero-ledger/hiero-consensus-node/tree/main/hapi

Solution

The hiero-consensus-node build (and potentially others) should be able to generate documentation as part of the Gradle build. For this, we need:

• Ideally, the source code of the proto2html.jar to turn that into a Gradle task
• A decision how to process the generated docs (e.g. should they be uploaded somewhere?). So that Gradle can do as much of the work as possible before the generated documentation files are picke up by a GH action.

Loosely related: #107

Alternatives

No response

[jsync-swirlds]

The proto files should be processed with the widely used protoc-gen-doc plugin to protoc to produce markdown. The major specification rework last year was targeted to this process using the template currently in the hedera-protobufs repository (which should be duplicated in the hiero-consensus-node repository).

If markdown needs to then be processed to html, there are existing gradle plugins for that purpose