Fix crash when setting debug visualization mode while gi is disabled (backport #3059)

[mergify]

🦟 Bug fix

Fixes #3058

Summary

When attempting to set the debug visualization mode, the code now checks if giis enabled. If gi is disabled, it logs an error and always sets the debug visualization mode to None to avoid a crash.
Setting a debug visualization mode while gi is disabled can cause a crash due to invalid or released resources. This change ensures safety by forcing the mode to None when gi is not active.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

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This is an automatic backport of pull request #3059 done by [Mergify](https://mergify.com).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 69.00%. Comparing base (b682e0a) to head (586888d).
⚠️ Report is 7 commits behind head on gz-sim8.

Additional details and impacted files

@@           Coverage Diff            @@
##           gz-sim8    #3073   +/-   ##
========================================
  Coverage    68.99%   69.00%           
========================================
  Files          342      342           
  Lines        33432    33432           
========================================
+ Hits         23068    23071    +3     
+ Misses       10364    10361    -3     

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