Clip the grid in the z-direction for SH LCFS fit metric

[geograham]

Description

Clip the equilibrium grid, so that the lower/upper-most coils are at the grid edges when inside the spherical harmonic approximation finding function. Prevents the use of an excessive number of required degrees in an approximation for cases where the LCFS appears to wrap around the divertor coils.

Checklist

I confirm that I have completed the following checks:

• Tests run locally and pass pytest tests --reactor
• Code quality checks run locally and pass pre-commit run --from-ref develop --to-ref HEAD
• Documentation built locally and checked sphinx-build -W documentation/source documentation/build

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 14 lines in your changes are missing coverage. Please review.

Project coverage is 80.32%. Comparing base (ca14b5e) to head (4f4d078).
Report is 17 commits behind head on develop.

Files	Patch %	Lines
...timisation/harmonics/harmonics_approx_functions.py	33.33%	14 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #3215      +/-   ##
===========================================
- Coverage    82.69%   80.32%   -2.38%     
===========================================
  Files          218      224       +6     
  Lines        23597    24741    +1144     
===========================================
+ Hits         19513    19872     +359     
- Misses        4084     4869     +785     

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[sonarcloud]

Quality Gate passed

Issues
3 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[github-actions]

⚠️ Warning Report

Found 0 new warnings, 0 fixed warnings. 🎉

All warnings (6)

On runtest

• /home/runner/miniconda3/envs/bluemira/lib/python3.10/site-packages/ffcx/element_interface.py:26: DeprecationWarning: Converting elements created in UFL to Basix elements is deprecated. You should create the elements directly using basix.ufl.element instead
• /home/runner/miniconda3/envs/bluemira/lib/python3.10/site-packages/basix/ufl.py:1909: DeprecationWarning: Converting elements created in UFL to Basix elements is deprecated. You should create the elements directly using basix.ufl.element instead
• /home/runner/miniconda3/envs/bluemira/lib/python3.10/site-packages/h5py/__init__.py:36: UserWarning: h5py is running against HDF5 1.14.3 when it was built against 1.14.2, this may cause problems
• /home/runner/miniconda3/envs/bluemira/lib/python3.10/site-packages/ufl/core/expr.py:275: DeprecationWarning: Expr.ufl_domain() is deprecated, please use extract_unique_domain(expr) instead.
• /home/runner/miniconda3/envs/bluemira/lib/python3.10/site-packages/ffcx/element_interface.py:23: DeprecationWarning: Use of elements created by UFL is deprecated. You should create elements directly using Basix.

On collect

• /home/runner/miniconda3/envs/bluemira/lib/python3.10/site-packages/ufl/core/ufl_type.py:56: DeprecationWarning: attach_operators_from_hash_data deprecated, please use UFLObject instead.