feat(tests-execute): EOA pkey support for stub account

[LouisTsai-Csie]

🗒️ Description

Originally, the stub file account only supported contracts, so we only provide contract addresses to the stub file. This becomes a problem when we want to do EIP-7702 interaction on-chain, which requires providing the private key of an EOA.

In the previous PR, we embed the private key in the test, which led to RPC issues (see PR #2617 ). This PR refactors everything into the stub account.

Add private key (pkey) support to stub configuration, enabling EOA stubs for benchmark tests that need tx signing (e.g., EIP-7702 authorization lists).

Stub file format change: entries are now objects with mandatory addr and optional pkey:

  {
    "contract_stub": {"addr": "0x..."},
    "eoa_stub": {"addr": "0x...", "pkey": "0x..."}
  }

When pkey is provided, the derived address is validated against addr at parse time.

🔗 Related Issues or PRs

PR #2617

✅ Checklist

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

  just static

• All: PR title adheres to the repo standard - it will be used as the squash commit message and should start type(scope):.
• All: Considered updating the online docs in the ./docs/ directory.
• All: Set appropriate labels for the changes (only maintainers can apply labels).
• Tests: Ran mkdocs serve locally and verified the auto-generated docs for new tests in the Test Case Reference are correctly formatted.
• Tests: For PRs implementing a missed test case, update the post-mortem document to add an entry the list.
• Ported Tests: All converted JSON/YML tests from ethereum/tests or tests/static have been assigned @ported_from marker.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.24%. Comparing base (4bf8bbe) to head (602d57c).

Additional details and impacted files

@@               Coverage Diff                @@
##           forks/amsterdam    #2624   +/-   ##
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  Coverage            86.24%   86.24%           
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  Files                  599      599           
  Lines                36984    36984           
  Branches              3795     3795           
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  Hits                 31895    31895           
  Misses                4525     4525           
  Partials               564      564           

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unittests	86.24% <ø> (ø)

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[marioevz]

Some comments, mainly cleaning up a bit of technical debt surrounding this feature.

[marioevz]

LGTM, much better, thanks for the changes!