Refactor RequestQueue and Expose in EsploraExplorer Constructor

[landabaso]

Overview

This PR introduces a major refactor of the RequestQueue and exposes it as a configurable parameter in the EsploraExplorer constructor. The changes aim to improve error handling and provide more control over request queue management in Esplora clients.

Key Changes

1. RequestQueue Refactor:

   • Added checks and thresholds for soft errors (HTTP 429, 50x) and hard errors.
   • Implemented a conservative approach by preventing new tasks from being added to the queue while handling errors.
   • Introduced parameters for configuring the RequestQueue, including:
     • maxAttemptsForSoftErrors
     • maxAttemptsForHardErrors
   • Added a function to generate randomized throttle times to avoid synchronized retry attempts.

2. EsploraExplorer Constructor:

   • Updated the EsploraExplorer constructor to accept RequestQueueParams.
   • Integrated the refactored RequestQueue into the EsploraExplorer instance.

3. Configuration Updates:

   • Adjusted constants and configuration for regtest, blockstream, and mempool space environments.

4. Tests and Fixtures:

   • Enhanced test coverage.

5. Version Bump:

   • Updated package version to 0.3.0 to reflect the significant internal changes and improvements.