fix: support for netcdf missing values

[b8raoult]

Description

Will address #208

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Issue Number

Code Compatibility

• I have performed a self-review of my code

Code Performance and Testing

• I have added tests that prove my fix is effective or that my feature works
• I ran the complete Pytest test suite locally, and they pass

Dependencies

• I have ensured that the code is still pip-installable after the changes and runs
• I have tested that new dependencies themselves are pip-installable.

Documentation

• My code follows the style guidelines of this project
• I have updated the documentation and docstrings to reflect the changes
• I have added comments to my code, particularly in hard-to-understand areas

Additional Notes

[gmertes]

LGTM , but since this is also touching the extract_lam output: @frazane would you have time to check that this is not breaking things for your lam setup?

[dietervdb-meteo]

extract_lam works now, at least in my setup. Don't know if @frazane wants/needs to check independently?

[dietervdb-meteo]

Succesfully tested by both @frazane and myself.

[gmertes]

Thanks for testing @dietervdb-meteo and @frazane !