Refactor/isolate worldstate

[asdacap]

• Move ITrieStore and IWorldState outside of INethermindApi. These should not be used directly as it will make swapping state layout very hard.
• Move healing related code and ISnapServer from Nethermind.Synchronization to Nethermind.State, exposing them from IWorldStateManager. These uses ITrieStore so, to hide ITrieStore, it need to be in IWorldStateManager. Also, paprika probably need to have a completely different snap server implementation.
• Move all pruning trie store state related initialization code into PruningTrieStateFactory. This should make it easier to be used in tests and make it clear, which part of the initialization is for the pruning trie store and hopefully prevent future exposure of trie store specific interface.

Types of changes

What types of changes does your code introduce?

• Refactoring

Testing

Requires testing

• Yes
• No

If yes, did you write tests?

• Yes
• No

Notes on testing

• Testing....

[Scooletz]

No input from my end. INodeStorage is still in the api, which in my understanding should be a subject of a further refactor when another storage (like Paprika) is used. Appreciate the removal of the TrieStore though.