refactor(tests): create fixture items for vm tests

[gurukamath]

🗒️ Description

This PR extends the pytest-based test infrastructure to cover VM, trie, and ethash tests, aligning them with the existing state and block test architecture. It also enables selective test execution based on changed files for both json_infra and optimized test environments in CI. This was previously enabled only for json_infra.

🔗 Related Issues or PRs

#1666

✅ Checklist

• All: Ran fast tox checks to avoid unnecessary CI fails, see also Code Standards and Enabling Pre-commit Checks:

  uvx tox -e static

• All: PR title adheres to the repo standard - it will be used as the squash commit message and should start type(scope):.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.00%. Comparing base (519eb26) to head (5404596).

Additional details and impacted files

@@               Coverage Diff                @@
##           forks/osaka    #1823       +/-   ##
================================================
+ Coverage        53.45%   87.00%   +33.55%     
================================================
  Files              743      743               
  Lines            44076    44076               
  Branches          3891     3891               
================================================
+ Hits             23559    38347    +14788     
+ Misses           20306     5224    -15082     
- Partials           211      505      +294     

Flag	Coverage Δ
unittests	87.00% <ø> (+33.55%)	⬆️

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