Third host port of the drawio skill, following the Codex pattern:
byte-identical skills/drawio/SKILL.md, host wrapping only. Copilot has no
folder-name rule, so plugins/copilot/ is itself the plugin root with a root
plugin.json (Copilot's manifest format, skills directory list).
Marketplace manifest at .github/plugin/marketplace.json (Copilot's primary
lookup path; it falls back to .claude-plugin/). Copilot's schema inlines
plugin metadata in the marketplace entry, so it mirrors plugin.json and the
two must be kept in sync. Explicit invocation is /drawio — Copilot does not
prefix plugin skills. Other Copilot surfaces (VS Code agent mode, coding
agent, code review) load the same skill from a repo's .github/skills/.
Extends the skill-sync CI check to enforce byte-identity for the new copy
and updates the host tables and cross-links in the affected docs.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Gaudenz Alder