Agent Skills: review-skill

Audit existing skills (SKILL.md files) against the write-skill authoring rubric — frontmatter validity, description trigger coverage, structural size, detection-rule over-fit, reference resolution, intra-skill cross-references. Use when reviewing a newly written skill, checking skill quality before merge, evaluating refactored or consolidated skills, or running a compliance pass over the skill plugin. Outputs findings classified as real gaps, observations, or pre-existing issues, each with a concrete recommended fix.