blueterra 0.2.0

blueterra 0.2.0\n\nThis version corrects map-unit annular BPI kernels for non-square cells, makes zero-variance normalized BPI return NA, adds coverage-fraction-weighted exact polygon summaries, records transect orientation concentration and corridor metadata, and adds functional verification.\n\nThe release source is tagged v0.2.0. A persistent archive DOI has not yet been assigned.