aihero.dev renders an install widget above every skill page. Each page
then repeated the same commands in its body, and the two copies had
drifted: the widget uses the current `npx skills@latest ...` wording
while the hand-written blocks mostly carried the older bare `npx skills
...`. Pages showed the right command and a stale one together.
Delete the block from all 25 pages and record the rule in
.agents/writing-docs.md: install wording belongs to the site, not the
page. The template no longer carries a Quickstart, and
.agents/install-block.md notes that docs pages are not one of its
consumers.
