analysis Directory Reference

Files
	footprint_check.hpp
	Footprint check against datasheet land patterns (issue #5, docs/05-routing.md §43, D115).
	footprint_ref.hpp
	Datasheet land-pattern references and the list of brands whose datasheets are trusted (issue #5, docs/05-routing.md §43, D115).
	region.hpp
	The reference copper of one layer as a queryable region (issue #7, docs/05-routing.md §42): the geometry of the return-path audit.
	return_path.hpp
	Reference-return audit of high-speed nets (issue #7, docs/05-routing.md §42, D114).