Hash of an empty trie: keccak256(RLP_NULL), a well-known Ethereum constant.
Hardcoded so it needs no lazy initialization, works in const contexts, and
pulls no lazy-cell dependency into no_std builds. The
empty_trie_hash_matches_keccak test pins it to the computed value.
Verifies that the key value range belongs to the trie with the given root given the edge proofs for the range
Also returns true if there is more state to be fetched (aka if there are more keys to the right of the given range)