refactor(storage): create StorageProtocol

[glevco]

Motivation

To externalize storage dependencies from the verification process, we need to inject a storage into some methods used in verification, so it can either receive a TransactionStorage (rocksdb), or a simple memory storage that will be implemented in next PRs. To unify both of them in a single interface, a Python protocol is introduced, StorageProtocol.

Acceptance Criteria

• Create StorageProtocol, a protocol for unifying a subset of storage methods.
• Add methods to TransactionStorage so it conforms to the StorageProtocol.
• Update DAA so its calculation depends on a StorageProtocol, and update usages accordingly.
• Update Reward Lock Transaction methods so they depend on a StorageProtocol, and update usages accordingly.

Checklist

• If you are requesting a merge into master, confirm this code is production-ready and can be included in future releases as soon as it gets merged

[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

❗ No coverage uploaded for pull request base (master@a653335). Click here to learn what that means.

Files	Patch %	Lines
hathor/manager.py	66.66%	0 Missing and 1 partial ⚠️

Additional details and impacted files

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  Misses            ?     2604           
  Partials          ?      669           

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