fix: surface clear error when venv's python version doesn't match con…

[IzaakGough]

Fixes #6626

[wiz-9635d3485b]

Wiz Scan Summary

Scanner	Findings
Vulnerabilities	-
Sensitive Data	-
Secrets	-
IaC Misconfigurations	-
SAST Findings	2  1
Software Management Findings	-
Total	2  1

View scan details in Wiz

To detect these findings earlier in the dev lifecycle, try using Wiz Code VS Code Extension.

[gemini-code-assist]

Code Review

This pull request introduces a Python version mismatch check that compares the configured runtime version with the actual version in the virtual environment's pyvenv.cfg file, throwing a clear error if they do not match. It also adds comprehensive unit tests for this new functionality. The review feedback suggests removing the Windows-specific exclusion check, as the pyvenv.cfg parsing is cross-platform and would benefit Windows users as well, which also allows for simplifying the associated unit tests by removing the platform stubbing.