chore: remove Waku v1 and wakubridge code

[jm-clius]

Description

This PR addresses the bulk of the changes necessary for #1767.

It removes the legacy Waku ("Waku v1") and Waku v1 <> v2 bridge ("Waku Bridge") code from the nwaku repo.
This touches a great many files, so I'll try to give reviewers some context about possible impact(s) under Changes.

The Waku v1 code is now maintained in https://github.com/waku-org/waku-legacy.
The Waku bridge code is now maintained in https://github.com/waku-org/waku-bridge.
Note that the waku-bridge repo requires some of the changes in this PR to be fully functional with working CI, although all necessary code has been moved. waku-legacy repo is complete, with functioning CI if any changes are to be made in future.

Scope of changes

• move all v1 code, examples and tests to waku-legacy
• move all bridge code, examples and tests to waku-bridge
• updated READMEs to reflect changes
• NB: remove wakunode1 from the release artifacts. From now one we won't include wakunode1 in releases.
• NB: removed all wakunode1 and wakubridge build tasks from the Makefile. This will affect Jenkins deployment jobs, such as https://ci.infra.status.im/job/nim-waku/job/deploy-bridge-test/, https://ci.infra.status.im/job/nim-waku/job/deploy-bridge-prod/ and https://ci.infra.status.im/job/nim-waku/job/deploy-wakuv1-test/
• Most NB: removed support for "v1" type payload encryption and decryption in nwaku, including removing the Private API from the JSON-RPC Relay API. This is potentially the most impactful change and would have to be reviewed with stakeholders before merging. Afaik this functionality is not used and not currently being planned anywhere. In order to keep this, the legacy waku code would have to be added as another submodule in nwaku, which I'd like to avoid if possible

What is excluded from scope?

Removing references to v2, e.g. changing import paths from waku/v2 to just waku/. This would clutter this PR even more, so will be done in a subsequent step.

What should be reviewed?

The impact of items marked as "NB" under Scope of Changes and any other high-impact consequences of removing v1 code that I might have missed.

[jm-clius]

Marking as ready for review, as:

• confirmed that Jenkins deployment is disabled for Waku v1 and not used for wakubridge
• confirmed from stakeholders that deprecated Private API is not roadmapped

[richard-ramos]

🥇

[SionoiS]

LGTM!

Do we keep track of who use what API somewhere? Would be useful to not forget ppl when communicating big changes.

[Ivansete-status]

LGTM! Thanks for this!
In the future, I think we should delete any reference to "v2" or "2" (e.g. wakunode2)

Also, I'd remove the 'v1' and 'v2' folders and put all the content underneath 'v2' right under the 'waku' folder, and just mention that in the CHANGELOG.md.

[alrevuelta]

@jm-clius thanks for this!!

[jm-clius]

In the future, I think we should delete any reference to "v2" or "2" (e.g. wakunode2)

Indeed. You'll see I mentioned that as excluded from scope in the description simply to keep this PR a bit more contained :)