- Demonstrates correct new API usage: Topology + Basis + IntegrationPoint separation
- Mock BasisValues struct with shape functions N and derivatives dN_dξ (SVector)
- Tests linear tetrahedron (P1, 4 nodes) evaluation at center and corner nodes
- Tests linear triangle (P1, 3 nodes) evaluation and partition of unity
- Validates constant derivatives for linear elements
- Integration with Gauss quadrature: evaluate_basis at all integration points
- Complete FEM workflow demonstration: Topology → Integration → Basis → Assembly
- Multiple element types from same topology (P1 vs P2 with same integration points)
- Type stability and zero allocation verification with StaticArrays
- 291 lines demonstrating separation of concerns: Topology ≠ Basis ≠ Integration