feat: Implement simple core msg facility

[georgi-l95]

Description

This PR implements the core plugin system for Rock Node, adding three essential plugins (Publish, Verifier, and Persistence) along with the necessary event handling infrastructure. The changes establish a robust event-driven architecture using the "Claim Check" pattern for efficient data handling between plugins.

Related Issues

• Closes Define Core Event Structs #16
• Closes Integrate Messaging Facility into AppContext #19

Changes

• [Core]: Added event types and BlockDataCache for plugin communication
• [Core]: Enhanced AppContext with event channels and cache management
• [Plugin System]: Implemented three core plugins:
  • PublishPlugin: Simulates block production and implements the Claim Check pattern
  • VerifierPlugin: Processes received blocks and verifies their contents
  • PersistencePlugin: Handles verified blocks and manages data persistence
• [Dependencies]: Added new dependencies:
  • dashmap for concurrent cache management
  • uuid for generating unique cache keys
  • Additional tokio features for async operations

Reviewer Checklist

• The code follows the project's coding standards.
• New and existing unit tests pass locally with my changes.
• I have added necessary documentation (if applicable).
• I have confirmed that this change does not introduce any new security vulnerabilities.