spatial Directory Reference

Files
	cell_list.hpp
	Cache-coherent 2D cell list for O(1) amortized neighbour queries.
	cell_list_3d.hpp
	Cache-coherent 3D cell list for O(1) amortized neighbour queries.
	connected_components.hpp
	Iterative BFS connected-component labelling.
	fields.hpp
	Forwarding shim — field types have moved to pde/fields.hpp.
	grid3d.hpp
	3D Cartesian scalar grid backed by num::Vector storage.
	pbc_lattice.hpp
	Precomputed periodic-boundary neighbor arrays for a 2D square lattice.
	spatial.hpp
	Umbrella include for spatial data structures.
	sph_kernel.hpp
	Dimension-generic SPH smoothing kernels.
	stencil.hpp
	Forwarding shim — stencil utilities have moved to pde/stencil.hpp.
	verlet_list.hpp
	Verlet neighbour list with skin-radius temporal caching.