Phase D3 of plan 2026-08-19 (decision S21): skills-local is the local test
bed; promote individually as each proves out. ms-unslop is the only one of
the seven local skills with working enforcement evidence — a checker
(tools/unslop-hook/unslop-check.js), a machine-source list (lists.json), a
19-test suite, a measured corpus, and a regression fixture.
The checker itself stays fleet-local for now (it binds to a specific
harness extension surface); this promotes the skill document only.
Gates verified on the moved file: sanitization denylist clean, prettier
3.8.1 clean (6730 chars was fred's measure at assignment; 7249 as shipped
today — both pass).