ECC-2317: Improve parsing comma-separated arguments

[joobog]

Description

This pull request addresses parsing improvements in the parse_keyval_string function to handle comma-separated values that may include nested JSON-like structures. It also introduces a new regression test to ensure correct behavior for this case and updates the test suite to include the new test.

Contributor Declaration

By opening this pull request, I affirm the following:

• All authors agree to the Contributor License Agreement.
• The code follows the project's coding standards.
• I have performed self-review and added comments where needed.
• I have added or updated tests to verify that my changes are effective and functional.
• I have run all existing tests and confirmed they pass.

[sawom666]

Another test should be added which combines the two forms separated by commas
e.g.,

grib_set -s year=1994,gridSpec='{blah,blah,etc}',month=5  in out

[joobog]

That’s a good point! Otherwise, the test wouldn’t be complete.

[sawom666]

Also check what we just set actually went through,

grib_check_key_equals out month 5
grib_check_key_equals out year 1994

etc

[sawom666]

And also the grid increment changes should be checked ( as a result of setting gridSpec key )
:)

[joobog]

For gridSpec, we’re adding a new systematic test. We’ll cover it there. Thanks a lot for improving the test!

[sawom666]

Beautiful 👍

[codecov-commenter]

Codecov Report

❌ Patch coverage is 83.33333% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 88.22%. Comparing base (e3694ee) to head (9a05acb).

Files with missing lines	Patch %	Lines
src/eccodes/grib_util.cc	83.33%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #533      +/-   ##
===========================================
- Coverage    88.22%   88.22%   -0.01%     
===========================================
  Files          854      854              
  Lines        63553    63559       +6     
  Branches     11290    11293       +3     
===========================================
+ Hits         56071    56075       +4     
- Misses        7482     7484       +2     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.