Activate ZIP 68 and clarify ZIP 203 to facilitate Zcash Lightning and programmable locks

our research on Violet’s Constrained Locks allows people to use FROST variations to successfully build t-of-n threshold conditional multisig locks that are composable in Zcash natively. However, relative timelocking is NOT supported in Zcash right now, and the current workaround requires us to expose the existence of the lock as a transparent input and output. As such, I request the community to unite and add the two changes: Ratify ZIP 68, allowing relative timelocking in Zcash. EDIT: ZIP 112, its companion, is also ratified. Clarify and enforce nLockTime for ALL transactions regardless of transparent inputs or not, indicated as in [protocol spec] [ZIP 203] Clarify how transaction lock times are handled · Issue #539 · zcash/zips · GitHub This would allow us to introduce fully private locks in Zcash that allow funds to be locked to a hash preimage, a time, and more, fully privately. More importantly, ratifying ZIP 68 combined with VCLs would allow us to complete the development of ELSA (Efficient Layer-2 Schnorr-based Apparition), a version of the Lightning Protocol that works