fix(browse-sh): fetch SKILL.md via /api/skills/{slug}+skillMdUrl

The catalog's sourceUrl points at github.com/browserbase/browse.sh,
whose underlying repository is not always public — most raw URLs derived
from it 404. Use the per-skill detail endpoint instead, which returns a
skillMdUrl CDN blob that reliably resolves to the SKILL.md text. Fall
back to a raw.githubusercontent.com sourceUrl if the detail call fails.

- tools/skills_hub.py: rewrite BrowseShSource.fetch() to resolve via
  /api/skills/{slug} -> skillMdUrl; drop the unreachable _to_raw_url
  helper; expose the resolved URL in bundle.metadata.skill_md_url.
- tests/tools/test_skills_hub_browse_sh.py: match the real catalog
  shape (name = task name, slug = host/task-id), exercise the
  detail-endpoint -> blob two-call flow, and add a fallback test.
- scripts/release.py: map kylejeong21@gmail.com -> Kylejeong2.

scripts/release.py

@@ -104,6 +104,7 @@ AUTHOR_MAP = {
     "147827411+EloquentBrush@users.noreply.github.com": "AhmetArif0",
     "97489706+purzbeats@users.noreply.github.com": "purzbeats",
     "hugosequier@gmail.com": "Hugo-SEQUIER",
+    "kylejeong21@gmail.com": "Kylejeong2",
     "128259593+Gutslabs@users.noreply.github.com": "Gutslabs",
     "50326054+nocturnum91@users.noreply.github.com": "nocturnum91",
     "52470719+gianfrancopiana@users.noreply.github.com": "gianfrancopiana",