Add SimplexIntersectBall convex body and tests

[maria-zaza]

Summary

This PR adds SimplexIntersectBall, a convex body representing the intersection of a simplex in H-representation with a unit ball.

The body models:

[
K = {x \in \mathbb{R}^d : Ax \le b,\ |x - x_0| \le 1}.
]

Implemented functionality

• dimension()
• num_of_hyperplanes()
• is_in(...)
• is_in_optimized(...)
• line_intersect(...)
• gc_intersect(...)
• gc_intersect_positive(...)
• gc_intersect_all_roots(...)
• compute_reflection(...)
• linear_transformIt(...)
• shift(...)

Tests added

Adds unit tests for:

• 2D simplex membership
• line intersection
• 3D tetrahedron membership
• great-circle interval computation
• positive great-circle intersection
• all great-circle roots
• incremental great-circle update against fresh recomputation
• reflection on a tetrahedron facet

Validation

Tested locally with:

cmake --build build --target simplexintersectball_test
cd build
ctest -R simplexintersectball --output-on-failure