Importing a skill from a github.com URL probes the commits API to
disambiguate slash-bearing refs. On self-hosted servers the IP is often
already over GitHub's 60-req/hour unauthenticated limit, so the very
first probe returns 403 and the previous code aborted the entire
import ("validating ref \"main/skills/pptx\": github API returned
status 403").
Two changes make this resilient:
* Forward GITHUB_TOKEN as a bearer token on every api.github.com request
via a new doGitHubAPIGet / addGitHubAuthHeader helper. With a token,
the limit becomes 5000 req/hour and the issue disappears entirely.
* When the API still returns 401/403/429 (no token, or limit exhausted
on the higher tier) treat the probe as indeterminate via
errGitHubAPIBlocked, keep trying remaining candidates, and finally
fall back to parseGitHubURL's optimistic single-segment split. This
covers the common case (single-word refs like "main") even when the
API is fully blocked. A warn log points operators at GITHUB_TOKEN.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Closes the functional gap the reporter hit on alchaincyf/huashu-design
(skills.sh/alchaincyf/huashu-design/huashu-design) without expanding
candidatePaths unconditionally, which would let an unrelated root
SKILL.md hijack a different skill URL in a multi-skill repo.
Try SKILL.md at the repo root before falling into the recursive tree
fallback added in #1432. Verify the frontmatter name matches the
requested skill so only genuine single-skill repos take the fast path.
For those repos this also shaves the recursive tree API call.
Also clarifies the candidate-path comment so the root case is
explicit.
