RFC: using on-chan address as adigital identity; signing

[Overtorment]

Since I'm working on a project that does both onchain and offchain, Im thinking of a way for a user to provide proof-of-funds (for example) for a Lapp.

Imagine, Lapp is doing some orders matchmaking on OTC exchange, and requires that user proves that he owns at least X btc. Lapp would then require a signature of that corresponds to some onchain address which has at least X btc.
For user it would look like a popup with a request to sign some string, If user aggrees, than he would be taken to a wallet (or address, whatever) selector to sign this string with.

Such signatures are a big part of OTC traders life. Webln could simplify that a bit.

[wbobeirne]

In my opinion the goal of WebLN is to utilize the lightning network, with little emphasis on the on-chain parts of it. I'm still somewhat hesitant on #16 (though am fine with it mostly as a holdover for the still mostly on-chain world of transactions on the web), but this seems awfully niche and specific beyond that. It also makes cold storage solutions a second class citizen, which is something I'd much rather promote than keeping any significant funds in your node's hot wallet.

Happy to hear other opinions on the subject, but I'd expect use cases like this to remain somewhat high friction due to the level of security people should be taking with their on-chain funds.

[juscamarena]

Considering higher value payments probably won't be reliable in near term, I'd think it'll still make sense for on chain to get some love for the foreseeable future. Unrelated but would bee nice to have say connect rpc command available as well through webLN, would make it easier to support bitrefill's channel opening service over joule on LND.