Trie: hash on commit

[Arkenan]

It is highly likely that we are hashing each time we make a modification to the trie. However, this is at risk of re-hashing when a node is modified multiple times. We should actually mark modified nodes as dirty and only hash the dirty nodes at the end and keep the other ones untouched.

Let's evaluate moving the cache to address by path instead of hash and marking the modified nodes as dirty instead to hash them only on commit.