- skills are found at any depth under the skills dir, so category-nested
layouts (skills/<category>/<id>/SKILL.md) vendor correctly; the folder
basename is the upstream id and the outermost SKILL.md wins over anything
nested inside a skill folder
- web-tree urls pointing directly at a type directory (.../tree/main/skills)
now map that directory as the type root instead of nesting it under the
default layout
- verified against the real github.com/mattpocock/skills repository
(36 skills across categories; include-selection by basename)
