fix(poly): fixed numerous bugs related to inconsistent system sizing with the reduced operator

this has restored the symmetry which we relied on before.

src/poly/utils/private/utilities.cpp

@@ -2,7 +2,7 @@
 #include "mfem.hpp"
 
 namespace serif::utilities {
-    mfem::SparseMatrix buildReducedMatrix(
+    mfem::SparseMatrix build_reduced_matrix(
         const mfem::SparseMatrix& matrix,
         const mfem::Array<int>& trialEssentialDofs,
         const mfem::Array<int>& testEssentialDofs
@@ -93,4 +93,11 @@ namespace serif::utilities {
 
         return A_new;
     }
+
+    mfem::Vector build_dof_identification_vector(const mfem::Array<int>& allDofs, const::mfem::Array<int>& highlightDofs) {
+        mfem::Vector v(allDofs.Size());
+        v = 0.0; // Initialize the vector to zero
+        v.SetSubVector(highlightDofs, 1.0); // Set the highlighted dofs to 1.0
+        return v;
+    }
 }