[Feat] Database checkpoints
See the linked issue for the rationale; this PR implements the direct checkpoints approach outlined there.
Closes https://github.com/ProvableHQ/snarkVM/issues/2707.
Filing as a draft, pending community feedback wrt the scope.
CC https://github.com/ProvableHQ/snarkOS/issues/3630
CI failed.
@kaimast the snarkOS PR has instructions which I'll convert into a doc for validators
Sounds good. I will approve once CI passes.
Plz resolve conflict with origin/staging and make tests pass
Not sure why we're still seeing the RocksDB build issue, it passes for me locally without the manual addition of CXXFLAGS="$CXXFLAGS -include cstdint" :thinking:.