Interpreter uses snarkvm

[mikebenfield]

No description provided.

[mikebenfield]

This still needs changes to the interpreter itself, and it depends on a SnarkVM PR of mine, so we won't be able to merge it for a while.

But I realized while updating const propagation last week that the interpreter's hashes and commits don't always produce identical results to SnarkVM, and decided to just change the Value type to wrap SnarkVM's Value and to call SnarkVM's hash and commit functions.

[mikebenfield]

Alright, here's an update. The two Values are unified into LeoValue, which wraps SnarkVM's Value. Const propagation is run again as a later optimization, propagating through let.

The interpreter is in a broken state at the moment, not completely converted to use the new LeoValue. I'll fix it in yet another update.

Some of the tests need to be checked up on, as they may be pointless or at least have different utility than before, now that const propagation does a lot more.