fix: passing istatus set for vertislevel and vertisheight mpas_atm

[hkershaw-brown]

Description:

MPAS_ATM user reported that 2m and 10m fields in the state were not being updated by filter when they had vertical localization switched on.

In get_close_state, state with VERTISSURFACE was being converted to VERTISHEIGHT but given a failing istatus so the distance was "far away" (1e9), and thus not updated in the assimilation.

This pull request adds a passing istatus to convert_vert_distrib_state to the cases that did not set an istatus:

• case (VERTISLEVEL)
• case (VERTISHEIGHT)

This istatus was a problem for get_close_state where the convert_vert_distrib_state is used, but not for convert_vertical_state (since that istatus is ignored).

The mpas state is in height (m) so the 3D state variables (non-surface) don't enter the case statement localizing in height (ztypein == ztypeout).

Note I added a note in case (VERTISSCALEHEIGHT) line 5050 because ztypein == VERTISSURFACE can never be .true. at that point in the code. I can pull this out and make a separate issue to keep track of that.

Fixes issue

fixes #756

Types of changes

• 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

Documentation changes needed?

• My change requires a change to the documentation.
  • I have updated the documentation accordingly.

Tests

I compared the state (no inflation) t2m variables before and after assimilation.
no difference = not updated
difference = updated.

Checklist for merging

• Updated changelog entry
• Documentation updated
• Update conf.py

Checklist for release

• Merge into main
• Create release from the main branch with appropriate tag
• Delete feature-branch

Testing Datasets

• Dataset needed for testing available upon request
• Dataset download instructions included
• No dataset needed

/glade/derecho/scratch/hkershaw/DART/Bugs/mpas_2m_10m/small_run (low res)
/glade/derecho/scratch/hkershaw/DART/Bugs/mpas_2m_10m/rundir this is the user case (high res)