generate_pack kept a private .gitignore parser whose cache ignored the
root it was asked about, and generate_db a copy of the shared one. Both
now read largefiles.load_registered_paths, cached per root. Test modules
whose main block preceded their last class end with it again.
In existence mode the builder packs a core's file at a destination the
platform declares and does not hold, and counts the declaration met.
verify now reads the same placement and reports it OK, so both sides
agree on the platform's count.
Abdessamad Derraz