Feature Enhancements and Bug Fixes

[gha3mi]

• Converted the basis_bspline_der function to a subroutine.
• Fixed NURBS derivative calculations.
• Added cmp_Xg() to evaluate the geometry points.
• Added generic method derivative2() to compute the second derivative of a NURBS objects.
• Added nearest_point2() to compute the nearest point on a NURBS object using optimization.
• Added Interfaces.
• Added new tests: fdm_curve.f90, fdm_surface.f90, fdm_volume.f90.
• Updated nearest_point_* examples to use the new nearest_point2() method.
• Made basis and derivative generic methods.
• Removed intel-classic from CI (ifort is deprecated).

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 17.52688% with 767 lines in your changes missing coverage. Please review.

Project coverage is 25.69%. Comparing base (6434ba8) to head (4144211).

Files	Patch %	Lines
src/forcad_nurbs_volume.f90	3.86%	348 Missing ⚠️
src/forcad_nurbs_surface.f90	4.39%	261 Missing ⚠️
src/forcad_nurbs_curve.f90	16.54%	116 Missing ⚠️
example/nearest_point_1d.f90	0.00%	17 Missing ⚠️
example/nearest_point_3d.f90	0.00%	15 Missing ⚠️
example/nearest_point_2d.f90	0.00%	10 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #16      +/-   ##
==========================================
- Coverage   27.43%   25.69%   -1.75%     
==========================================
  Files          33       36       +3     
  Lines        3382     4183     +801     
  Branches      306      346      +40     
==========================================
+ Hits          928     1075     +147     
- Misses       2385     3039     +654     
  Partials       69       69              

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