The per-skill sidebar tree from PR #26646 emitted category entries with
only a label. Docusaurus derives translation keys from the label
(sidebar.docs.category.<label>), and categories that exist in both
Bundled and Optional (productivity, mcp, mlops, research, email,
software-development, dogfood) collided on identical keys — failing
i18n extraction and the Deploy Site build. Result: source had the
sidebar fix but no per-skill page rendered with a sidebar in production.
Add a 'key: skills-<source>-<category>' attribute to each generated
category dict so Bundled vs Optional get distinct translation keys.
Regenerated sidebars.ts via the script. Local docusaurus build passes.
a31191c3f5