chore: Reorganize RestApi specs for live documentation

[NagyZoltanPeter]

Background

Currently waku rest-api specification files (openapi.yaml's) are living next to the code separated by endpoints.
Also nwaku and go-waku maintains separately these open-api descriptors, rest endpoint types are not shared but sometimes duplicated.
This does not allow us to generate a comprehensive one source of truth documentation on the fly.
Such documentation can help waku users to build their solution on top of it vie utilizing rest api services. Just like bounty hackers can implement their UI with help if it.

Details

While obvious solution would be to merge all the descriptors under one big openapi.yaml file it would be hard to maintain and overview.
Target would be to route all these api descriptions from one root file yet separated by endpoints and schemas as OpenApi spec allows.
Another target is to find solution for a living documentation generated right from the nwaku master branch, possible embeddable into other waku documentation.

Acceptance criteria

No code change is made under this issue, only api spec files.

[ ] A working demo of api documentation right from nwaku repository.

[NagyZoltanPeter]

Weekly Update

• achieved: Http RestAPI interface is in parity with json-rpc with even more features supported on it.
• next: Openapi specification is reorganized and online doc generated out of it. Currently under PR review.
  Follow up spec reorganization with rest api type reorganization. RFC changes to enhance lighpust failure response.

[NagyZoltanPeter]

Effort on this - Rest API specification reorg is stopped.
As a last step the specification in its new form is moved to new repository: https://github.com/waku-org/waku-rest-api
Pull requests #2124 findings and remarks are to be followed up later here in align with go-waku.

@chair28980: Moved this to icebox from review due we decided to down-prio rest api efforts on nwaku till gen0 ready.
Please consider future task separation and priority of this effort.

[NagyZoltanPeter]

This is obsolate. We have it working from separate repository: https://github.com/waku-org/waku-rest-api
page is accessible: https://waku-org.github.io/waku-rest-api