chore: reorganize rest-api types

[NagyZoltanPeter]

Background

While rest api nwaku implementation is segregated by endpoints they implements their own types one-by-one.
This can be misleading adds complexity by code duplication and does not reflects one rest-api for Waku node as common.

Details

Ongoing task #2120 track normalize of openapi specifications and documentation.
This task tries to address and follow up that changes.

[ ] Reorganize types into common place
[ ] Remove type duplications
[ ] Enforce common naming scheme
[ ] Easy marshalling/de-marshalling code for api types, remove duplications of code/copy-pastes

Acceptance criteria

[ ] No change in functionality
[ ] All tests are passed
[ ] Alignment with go-waku and js-waku done in case of naming changes on api level.

[chair28980]

@NagyZoltanPeter I assigned this issue to you please update if thats incorrect, thank you!

[NagyZoltanPeter]

Weekly Update

• achieved: Enhancements on Rest request error handling.
• next: Finalize api spec and doc after PR review. Work in progress: rest api type reorganization. RFC changes to enhance light-push failure response.
• blocking: Fixing found issues during release.

[NagyZoltanPeter]

Block while come to decision on rest api spec changes.
Also it is low prio compared to gen0 tasks.

[NagyZoltanPeter]

Downprio!
Rest api specification is moved to https://github.com/waku-org/waku-rest-api
Original PR of spec effort: #2124 had several comments that effects rest-api types and interfaces. Until those are not agreed and applied to the specification this issue can be postponed.

[NagyZoltanPeter]

• Time gone by:
• rest api spec is moved and has its own reference UI.
• API types had been evolved and necessary reorg had been done meanwhile.

This is not applicable for current code base.