[Utility][Persistence][Savepoints/Rollbacks] Implement Snapshots - Persist SavePoints

[deblasis]

Objective

Implement a deterministic way to create a snapshot of the "World State" (technically a persisted version of what in the Design Document is referred as savepoint).

Origin Document

#493 and #562

Goals

• When a snapshot creation is triggered, the node should pause the normal operation (use state-machine and bus to coordinate with all the modules)
• When the snapshot is completed (OK or KO), normal operation should resume (the node should sync to catch up with what happened while it was snapshotting)
• Implement a way to provide feedback to the caller (RPC->CLI) about the progress and status of the operation
  • The same mechanism can be used for rollbacks and polled by the CLI right after the create snapshot (or rollback to snapshot) command is triggered
• The last valid/persisted height should be used as datasource for the snapshot
• The snapshot should be saved to the filesystem into a folder that's defined in Persistence configuration but we should keep an open mind regarding the future introduction of multiple destination types that are filesystem-like (Tor, FTP, S3, etc.). Using a simple abstraction should be enough for now, see related tickets for the whole context.
• The snapshot should be compressed
• The snapshot should be named meaningfully (append at least the height it refers to using a standardized naming convention that we'll have to put in the various documentation as well)

Deliverable

• A PR with implementation tending to the goals above
• Tests

Non-goals / Non-deliverables

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