c50d96e added a repair pass ahead of the demosaic and no document said
so: FR-RAW-3's text names levels, the CFA and the colour matrices, and
architecture.md §5.2's stage diagram went from the upload straight to
black and white levels.
FR-RAW-3 now carries a status note: what counts as hot or dead, what
the photosite becomes, that Bayer and X-Trans share the pass, that
export and every other demosaicing path get it with no setting, the
test that holds it, and that the DNG defect map dr-decode can read is
still not used. §5.2 gains the stage and a paragraph on why it sits
before the demosaic, and its pointer to the raw histogram's tap names
the demosaic box rather than a row count the new stage would have made
wrong.