check-versions.mjs reported "12 SKIP, exit 0" on a fresh clone with no
sibling plugin repos — a run that verified nothing was indistinguishable
from a clean run. Any SKIP now fails the gate by default (--allow-skip
opts in explicitly), and the summary always reports "verified N/M".
Also adds a homepage-resolves check on plugin.json (dead-link ERROR,
verified live against voyage's stale pre-polyrepo URL); the field stays
optional since 11 of 12 plugins don't carry it yet.
gateOutcome is split out as a pure function so both directions (all-SKIP
fails, fully-verified-clean still passes) are unit-tested without needing
a real sibling-repo layout on disk.
Kjell Tore Guttormsen
0b0bf24137