Add Grib 41

[SebastianThomas]

Description of Changes

This PR only adds support for the 4.41 Template type. It is basically a copy of the other types, but following the structure doc 4.41: https://www.cosmo-model.org/content/model/cosmo/grib/pdtemplate_4.41.htm

Has been tested on a File provided by MeteoSwiss: ICON CH2 OGD -> Parameter POACsnc (CTRL), e.g., here (may be out of date when reviewing).

Disclosure: The test case has been generated with AI following the structure of the PDS 4.40 test case.

PR Checklist

• Link to any issues that the PR addresses
• Add labels
• Open as a draft PR
  until ready for review
• Make sure GitHub tests pass
• Mark PR as "Ready for Review"

[lesserwhirls]

This looks great, and thank you for including a test! The only change I would make is to remove the full grib2 file and only include the GRIB index file. The .gbx9 file contains everything in the GRIB message except the data blocks. In the past, there have been questions about licensing of the data and the ability to redistribute, even for testing purposes.

[lesserwhirls]

It looks like the code style check started failing with your last change. You can fix this fairly quick by running ./gradlew spotlessApply (it can be a little annoying). I'll go ahead and merge this is and fix the formatting on my next PR. Thank you for the contributions!