Change Brunt-Vaisala frequency vertical dimension and fill boundary values

[mwarusz]

Motivated by the discussion in #394, this PR changes the Brunt-Vaisala frequency vertical extent to NVertLayersP1, since it is a field that is located on interfaces. However, instead of filling the top and bottom interfaces with zeros or fill value, this PR sets these boundary values to values from the closest interior interface. This can be seen as equivalent to using one-sided differencing to calculate the boundary value, and is what is used in MPAS-O when the surface value of Brunt-Vaisala frequency is needed by the submesoscale eddy parametrization.

Checklist

• Linting
  • Pre-commit run locally
• Building
  • CMake build does not produce any new warnings from changes in this PR
• Testing
  • Add a comment to the PR titled Testing with the following:
    • Which machines CTest unit tests
      have been run on and indicate that are all passing.
    • The Polaris omega_pr test suite
      has passed, using the Polaris e3sm_submodules/Omega baseline
    • Document machine(s), compiler(s), and the build path(s) used for -p for both the baseline (Polaris e3sm_submodules/Omega) and the PR build
    • Indicate "All tests passed" or document failing tests

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

[mwarusz]

Testing

CTest unit tests

• Machine: frontier
• Compiler: craygnu-mphipcc
• Build type: Release
• Result: All 40 tests passed
• Log: /lustre/orion/cli115/scratch/mwaruszewski/omega-pr-testing/bvf-nvertp1/build-craygnu-mphipcc/Testing/Temporary/LastTest.log

Polaris omega_pr suite

• Baseline workdir: /pscratch/sd/m/mwarusz/omega-pr-testing/bvf-nvertp1/baseline-gnu/
• Baseline build: /pscratch/sd/m/mwarusz/omega-pr-testing/bvf-nvertp1/baseline-gnu/build
• PR build: /pscratch/sd/m/mwarusz/omega-pr-testing/bvf-nvertp1/build-gnu
• PR workdir: /pscratch/sd/m/mwarusz/omega-pr-testing/bvf-nvertp1/pr-gnu
• Machine: pm-cpu
• Compiler: gnu
• Build type: Release
• Log: /pscratch/sd/m/mwarusz/omega-pr-testing/bvf-nvertp1/pr-gnu/polaris_omega_pr.o52837000
• Result: All tests passed