rpc!: change tweakfedpegscript to output both p2wsh and p2shwsh addresses

[delta1]

Changes tweakfedpegscript to return both p2wsh and p2shwsh version of
the tweaked address.

"address" has been removed from the tweakfedpegscript RPC result and replaced with "p2wsh" and
"p2shwsh" addresses.

[jsarenik]

Tested ACK a4eeed9

[jsarenik]

NACK a4eeed9, have read the diff

[jsarenik]

p2shwsh seems very non-standard and I do not know what is meant by that. Did you mean following?

sh(wpkh), Nested Segwit, P2SH-segwit
(all above are the same thing, how people call it, better do not add another)

[delta1]

It's wrapped segwit.

https://river.com/learn/terms/w/wrapped-segwit/

[tomt1664]

Tested ACK 5d64e89

[jsarenik]

It's wrapped segwit.

https://river.com/learn/terms/w/wrapped-segwit/

Thanks for the link.

One can not find it in Bitcoin Core nor in Elements Core doc and there's nothing like term "wrapped segwit" in the sources making the words ungreppable in the repo.

I just think that calling the same thing in multiple different ways may be confusing for the newcomers.

Update: there's a mention on a very long line here:

elements/doc/external-signer.md

Line 91 in 6d29a59

A future extension could add an optional return field with device capabilities. Perhaps a descriptor with wildcards. For example: `["pkh("44'/0'/$'/{0,1}/*"), sh(wpkh("49'/0'/$'/{0,1}/*")), wpkh("84'/0'/$'/{0,1}/*")]`. This would indicate the device supports legacy, wrapped SegWit and native SegWit. In addition it restricts the derivation paths that can used for those, to maintain compatibility with other wallet software. It also indicates the device, or the driver, doesn't support multisig.

And

elements/doc/release-notes/release-notes-0.16.0.md

Line 161 in 6d29a59

* A new field `iswitness` is True for P2WPKH and P2WSH addresses ("bc1..." addresses), but not for P2SH-wrapped segwit addresses (see below).

And although not self-standing

elements/doc/release-notes/release-notes-0.18.0.md

Line 432 in 6d29a59

P2SH-wrapped segwit addresses will continue to be provided if the user

So I've just never seen it in Bitcoin context yet.