feat(linear-static-3d-euler-beam): step 21 - load-assembly

include/fesa/assembly/load_assembler.hpp

@@ -0,0 +1,24 @@
+#pragma once
+
+#include "fesa/analysis/analysis_model.hpp"
+#include "fesa/fem/dof_manager.hpp"
+#include "fesa/math/sparse_matrix.hpp"
+#include "fesa/math/vector.hpp"
+
+namespace fesa {
+
+// Assembles only semantic nodal CLOAD records and forms the eliminated free
+// right-hand side; stiffness factorization remains an analysis responsibility.
+class LoadAssembler {
+public:
+    static Result<Vector> assembleFullNodalLoad(
+        const AnalysisModel& model,
+        const DofManager& dofs);
+    static Result<Vector> effectiveFreeRhs(
+        const Vector& fullLoad,
+        const SparseMatrix& kfc,
+        const Vector& prescribedValues,
+        const DofManager& dofs);
+};
+
+} // namespace fesa