feat: Introduce TransportError

[isSerge]

Summary

This PR introduces TransportError and replaces anyhow errors in send_raw_request methods.
This is a necessary step to improve error parsing, briefly discussed in #242

Testing Process

Checklist

• Add a reference to related issues in the PR description.
• Add unit tests if applicable.
• Add integration tests if applicable.
• Add property-based tests if applicable.
• Update documentation if applicable.

[codecov]

Codecov Report

Attention: Patch coverage is 93.77778% with 14 lines in your changes missing coverage. Please review.

Project coverage is 96.0%. Comparing base (05a1b54) to head (604b5ff).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...services/blockchain/transports/endpoint_manager.rs	84.0%	8 Missing ⚠️
src/services/blockchain/transports/error.rs	96.5%	6 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #259     +/-   ##
=======================================
- Coverage   96.0%   96.0%   -0.1%     
=======================================
  Files         66      67      +1     
  Lines      20002   20206    +204     
=======================================
+ Hits       19213   19404    +191     
- Misses       789     802     +13     

Flag	Coverage Δ
integration	59.5% <84.3%> (+0.3%)	⬆️
properties	20.7% <0.0%> (-0.3%)	⬇️
unittests	85.3% <75.1%> (-0.1%)	⬇️

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[shahnami]

Looks good! Thanks for the improvement.

Could you just tackle a few of the missing coverage lines in endpoint_manager?

They seem like an easy-win for our overall coverage.

[NicoMolinaOZ]

LGTM! thanks @isSerge!

[isSerge]

@shahnami I have added additional test for TransportError::UrlRotation, but not sure I can cover TransportError::RequestSerialization - it is quite difficult (if possible) to simulate this error within current setup