Add immutable MITC4 drilling selection and direct director springs

src/fesa/elements/mitc4_shell.cpp

@@ -12,6 +12,7 @@
 #include "math/finite_values.h"
 #include "math/vector3_operations.h"
 #include "elements/shell_kernel_values.h"
+#include "elements/mitc4_drilling_internal.h"
 
 namespace fesa {
 
@@ -1002,6 +1003,7 @@ Mitc4Shell::Mitc4Shell(std::array<Vector3, 4> coordinates,
       thickness_{thickness},
       youngs_modulus_{youngs_modulus},
       poisson_ratio_{poisson_ratio},
+      drilling_mode_{mitc4_drilling_internal::kProductionDrillingMode},
       source_location_{std::move(source_location)},
       identity_{std::move(identity)} {}