Threshold (FROST) custody for shielded ZEC: design check before a ZCG application

Quick one, nothing new to reply to yet, just flagging two things.

@conradoplg the issue’s up: zcash-sign: Ironwood (NU6.3 / v6) external signing — scoping, and the orchard FVK blocker · Issue #591 · ZcashFoundation/frost-tools · GitHub. Laid out where the version bump lands, orchard included. Still happy to do it if you’d rather point me at a branch than write it yourself.

@hanh separately, I’m filling out the application now. Fingers crossed it lands somewhere, and if it does I’d still take you up on the format question whenever you get a minute.