Refactors triangle calculations for generic vectors

Updates the `Triangle` class to use a generic `Vector` type instead of `Vector3`, enhancing flexibility and reusability.

Changes include updating relevant function return types to use `Vector::ContainedType` and adapting length and distance calculations accordingly.

This refactoring supports the ongoing work on the EPA algorithm (feature/epa_algorithm) by providing a more adaptable foundation for geometric calculations.

include/omath/linear_algebra/vector2.hpp

@@ -19,6 +19,7 @@ namespace omath
     class Vector2
     {
     public:
+        using ContainedType = Type;
         Type x = static_cast<Type>(0);
         Type y = static_cast<Type>(0);