[Utility][Persistence][Savepoints/Rollbacks] Refactor `UtilityContext` into `UtilityUnitOfWork`

[deblasis]

Objective

Create the logical abstraction that would represent the "Unit Of Work" (inspired by Martin Fowler's work in his "Patterns of Enterprise Application Architecture")

These abstraction should have specific implementations for Leader and for Replica nodes in order to allow a clean separation of concerns while keeping a degree of composability/reusability of the code. (Lower level requirement discovered while working on #508)

Origin Document

This is part of a rescoping of the tickets related to SavePoints, Rollbacks and it originates essentially from the following tickets:

• [Core] Create design document for save points and rollbacks #493
• [Persistence][Utility] Separate all CreateAndApply functions into more functional components #508

Goals

• Refactor UtilityContext to be a polymorphic UtilityOfWork
• Introduce LeaderUtilityUnitOfWork and ReplicaUtilityUnitOfWork that expose the methods that are going be to used depending on the "role" of the node in the consensus process applying the SOLID principles.

Deliverable

• Refactored UtilityOfWork
• LeaderUtilityUnitOfWork and ReplicaUtilityUnitOfWork implementations
• Logical switch/factory method to use the correct UOW (Unit Of Work) depending on the node's role

Non-goals / Non-deliverables

• Changes in logic (at this point, the code should be functionally equivalent to the previous implementation)

General issue deliverables

• Update the appropriate CHANGELOG(s)
• Update any relevant local/global README(s)
• Update relevant source code tree explanations
• Add or update any relevant or supporting mermaid diagrams

Testing Methodology

• Task specific tests or benchmarks: make ...
• New tests or benchmarks: make ...
• All tests: make test_all
• LocalNet: verify a LocalNet is still functioning correctly by following the instructions at docs/development/README.md

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Creator: @deblasis
Co-Owners: @Olshansk

[deblasis]

I have already developed the code that should close this issue, I need to extract a PR that's coming after I finished rescoping

[jessicadaugherty]

Please reference #352 in implementation to avoid complications with business logic dependencies.

[Olshansk]

Interested to see what the design & implementation of this will look like.

Side note: The link to the book is broken. Is it something you'd recommend?

[deblasis]

Side note: The link to the book is broken. Is it something you'd recommend?

I had to read it years ago, it was like mandatory for architecting .NET financial applications. There's a lot of C# and/or Java code but most of the ideas are still solid IMHO.