Zero-reference proof passed: no *.csproj/*.props/*.targets/*.slnx names any
of the 7 binaries; no <HintPath> element exists repo-wide. Build clean after
removal. Added lib/ to .gitignore to block re-introduction.
Out of scope: purging these from git *history* (BFG/filter-repo) is a separate,
heavier decision that rewrites every clone; this removes them from the tip only.
Joseph Doherty
d6ae8bd03a