add channel v1 duck type to spec

[vaikas]

Add v1 channelable to the spec.

Proposed Changes

• Add v1 channelable to the spec.

Release Note

- 🧽 Update or clean up current behavior
Update the spec to include v1 of the channelable.

Docs

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This pull-request has been approved by: vaikas

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[pierDipi]

Do we need to update the changelog section as well?

/lgtm
/hold

unhold if this can be done in another PR (please, open an issue to track this).

[vaikas]

@Harwayne Did you cut the release yet, or will this make it? I wouldn't hold the release, but to address the release notes question. If this won't make the cut, it will go out in the next . release and will hence get added to release notes for it, so that should all be good? If you already cut the release, please unhold.

[vaikas]

.17 was already cut, this missed it, so I'm unholding and it will go in the . release.
/unhold

[vaikas]

/hold cancel