feat: transaction outcome proof verification with composition

[austinabell]

** Experimental, do not use in production **

• Switches the example to use recent live data, rather than an old scraped vector.
• Implements program to verify a transaction outcome proof, composed with the light client proof
• Bump zkvm version to 0.21

There is a strange issue relating to the outcome RPC proofs to resolve to the block hash rather than the block merkle root. I've asked about it here https://near.zulipchat.com/#narrow/stream/295558-core/topic/Outcome.20proof.20block.20root.20inconsistency/near/435204661

TODO:

• Resolve above issue
• Resolve types duplication at some point (they indicated they are doing a refactor to remove the bloat that also makes it incompatible to compile the core types in the zkVM, there are some unideal hacks)
• Add License and headers