fix(cli): check access process on windows

[SMoraisAnsys]

Description

When running on windows, the process username() can contain the DOMAIN which makes the comparison fail.

Issue linked

None

Checklist

• I have visited and read Develop PyMAPDL.
• I have tested my changes locally
• I have added necessary documentation or updated existing documentation.
• I have followed the PyMAPDL coding style guidelines.
• I have added appropriate unit tests that also ensure the minimal coverage criteria.
• I have reviewed my changes before submitting this pull request.
• I have linked the issue or issues that are solved to the PR if any.
• I have assigned this PR to myself.
• I have marked this PR as draft if it is not ready to be reviewed yet.
• I have made sure that the title of my PR follows Commit naming conventions (e.g. feat: adding new MAPDL command)

[Copilot]

Pull Request Overview

This PR fixes a Windows-specific bug in the process access check where username comparison fails when the process username includes a domain prefix (e.g., "DOMAIN\username"). The fix extracts the username portion after the backslash on Windows systems.

Key changes:

• Added platform-specific handling for Windows usernames in _can_access_process()
• Extracts username from "DOMAIN\username" format by splitting on backslash

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[germa89]

I forgot to mention, you should add a test for this please :)

[codecov]

Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 91.34%. Comparing base (be80897) to head (9a30857).
⚠️ Report is 3 commits behind head on main.

❌ Your patch status has failed because the patch coverage (66.66%) is below the target coverage (90.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4293      +/-   ##
==========================================
+ Coverage   91.28%   91.34%   +0.06%     
==========================================
  Files         193      193              
  Lines       15742    15745       +3     
==========================================
+ Hits        14370    14383      +13     
+ Misses       1372     1362      -10     

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[SMoraisAnsys]

@germa89 The current implementation of the tests do not allow me to test without having mapdl installed (or that's my understand from the need to provide a path for ansysxxx). Would you like me to update the current test so that it patches a few pymapdl commands and runs without requiring any local install ?

[germa89]

Thank you @SMoraisAnsys for this PR. It does fix one our current issues that went unnoticed.

Also sorry for the delay to get to this.

LGTM.

Close #4321