Fix LFRic time coordinate metadata

[jwarner8]

Fixes LFRic coordinate metadata, by adding forecast_period and forecast_reference_time, summarised in #1113

Contribution checklist

Aim to have all relevant checks ticked off before merging. See the developer's guide for more detail.

• Documentation has been updated to reflect change.
• New code has tests, and affected old tests have been updated.
• All tests and CI checks pass.
• Ensured the pull request title is descriptive.
• Conda lock files have been updated if dependencies have changed.
• Attributed any Generative AI, such as GitHub Copilot, used in this PR.
• Marked the PR as ready to review.

[github-actions]

[jfrost-mo]

A small observation. Let me know when you want a proper review on this.

[jwarner8]

A small observation. Let me know when you want a proper review on this.

THanks, did you say you were working off this branch for a more general cube time merge fix?

[jfrost-mo]

I'll get this reviewed and merged first.

[jfrost-mo]

Looks good to me. The comments are minor formatting things, and I'm happy for you to merge after addressing them.

[jfrost-mo]

Some additional tests are needed.

[jwarner8]

Update 11/02: Have added tests, but some are not raising the correct errors as expected by pytest.

[jwarner8]

I have fixed the tests, weirdly the LFRic cube (slammed_lfric_cube_readonly) already had forecast_reference_time and forecast_period. Anyway, ready for review now @jfrost-mo and to base your merge nc/pp fixes from.

[jwarner8]

I have significantly rewritten the callback to use more conditionals rather than try except blocks, as read will take various data with missing coords and we dont want to keep raising keyerrors. So its more of a defensive function that tests if coords exist before proceeding to next step. cube.attributes returns empty list if no attributes, so shouldn't throw up errors in if "time_origin" in tcoord.attributes:

Now ready to review now this is more defensive

[jfrost-mo]

Overall looking sensible. A couple code changes suggested, mainly to the tests.

[jfrost-mo]

LGTM

[jfrost-mo]

There are some conflicts though. Are you happy to fix them or shall I?

[jwarner8]

This branch has no conflicts with the base branch

Hmm, I see "This branch has no conflicts with the base branch"

[jfrost-mo]

Strange. Try merging it; hopefully it is just on my end.