craftbot-skill-improve

Refine an existing CraftBot skill using evidence from one completed task that used it. Read the per-task SKILL_SOURCE markdown the handler wrote, diff it against the existing SKILL.md, apply surgical edits to skills/<target>/SKILL.md. Use this when CraftBot has spawned an 'Improve Skill' workflow task and you need to refine the skill's accuracy or token efficiency without redesigning it.