migrate from ecdsa and secp256k1 to coincurve

[prusnak]

i think we should just migrate to coincurve - it is well maintained (last secp256k1 release was in 2021) - and even CLN uses coincurve and not secp256k1 for their python plugins

it would be great to also drop the ecdsa dependency and use only coincurve

[michael1011]

I've never been a fan of this library coming with a signature library by default. How about switching to coincurve and making it optional?

[prusnak]

I want to reduce the number of libraries used by lnbits, not to increase it.

Now I understand it better what you meant. Yes, makes sense! 👍

[prusnak]

Done in #46 and released via 2.1.0