Enable Bitcoin Contracts for Devnet/sBTC Devenv

[radicleart]

Feature request

Can Bitcoin Contracts be enabled with sBTC Devenv and Devnet networks ?

This will unlock local development against regtest with sBTC and DLC.

Currently this seems to be switched off

[sosaucily]

Working on something similar currently #4270

[markmhendrickson]

@radicleart would regtest work for you here per that PR's work?

[radicleart]

Hey yes - i got it working on regtest - I changed the check in the wallet from checking for testnet to checking for not mainnet and then making a local build.

Its one line change see

[kyranjamie]

I have a feeling this relates to @Polybius93's work here to enable custom Bitcoin network URLs. He's done a PR here, but it's been blocked by some other changes that are needed.

I'm going to take a look at this this morning and see if I can get it closed.