A .skill archive is a zip file containing exactly one top-level skill
directory. The argument to the install command must be an absolute path ending
in .skill. For example:
/tmp/reviewer.skill
The archive layout should look like:
reviewer/
reviewer/SKILL.md
reviewer/scripts/check.py
reviewer/REFERENCE.md
The archive is rejected when:
- the path is relative;
- the file is not a valid zip archive;
- the archive contains zero or multiple top-level directories;
- an entry uses an absolute path; or
- an entry contains
..and could escape the extraction root.