Fix sphere smoothing

[wilfonba]

Description

This PR fixes a bug in the smoothing function for spherical patches that was identified during IGR development. The smoothing was only being applied inside the nominal radius of the patch, resulting in a grid level discontinuity. The old code generates the following IC

Which shows smoothing only on the sphere's interior and a discontinuity on the outer surface. The new code generates the following IC

which shows smoothing on both sides of the nominal radius of the patch. The smoothing coefficient for both ICs is identical.

Fixes #(issue) [optional]

Type of change

• Bug fix (non-breaking change which fixes an issue)

Scope

• This PR comprises a set of related changes with a common goal

[wilfonba]

@haochey Says this is likely an issue for some other patches as well and he's going to resolve it in this PR.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 11 lines in your changes missing coverage. Please review.

Project coverage is 43.74%. Comparing base (131b41e) to head (105f30a).

Files with missing lines	Patch %	Lines
src/pre_process/m_patches.fpp	0.00%	11 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #798   +/-   ##
=======================================
  Coverage   43.74%   43.74%           
=======================================
  Files          65       65           
  Lines       19039    19039           
  Branches     2332     2332           
=======================================
  Hits         8328     8328           
- Misses       9303     9305    +2     
+ Partials     1408     1406    -2     

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[sbryngelson]

@haochey let me know when this is ready