fix(HYBIM-849): rename local variables to avoid shadowing

[shuningc]

Summary

• Rename version → py_version in test_setup.py to avoid shadowing the outer version name
• Rename log → logger_instance in experiments.py to avoid shadowing the module-level _logger
• Rename version → version_str in headers_data.py to avoid shadowing the imported version from get_package_version()

[fercor-cisco]

🤖 This review was generated by the Astra agent (claude-opus-4-8). It may contain mistakes.

Verdict: approve — Purely local-variable renames to remove shadowing; all references updated correctly and no behavior change.

General Comments

• 🔵 nit (documentation): The PR description states the log → logger_instance rename avoids "shadowing the module-level _logger", but the local log actually shadowed the imported log decorator from splunk_ao.decorator (imported at experiments.py line 14, used at line 246), not _logger. The rename itself is correct and beneficial — only the stated rationale is inaccurate. Worth correcting in the description to avoid future confusion.