The false green: script/lint chaining a second docker build after the
lint image ran prettier twice and counted once. The misresolution: a
bare docker build followed by cp -f resolved to the cp's file. Pin
both, and each separator that bounds an invocation.
edgesOf used a single test/exec for docker build, so a line with two
builds produced one edge and the file flag was searched across the whole
line. Follow every occurrence with matchAll and slice each one to the
next shell separator before looking for its flag.
Also correct the README's claim that script/fmt-check is the one
formatting path left on the host.
user