### Context
Our TS check GHA occasionally runs into GH rate limits because of
`fetchAgentSkills`
### Changes involved
- Opting to omit `fetchAgentSkills` for typecheck
- `generateStaticContent` is needed still afaict
- Allow GITHUB_TOKEN to be passed for `generateStaticContent`
- And pass that env var from `typecheck.yml`
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
## Summary by CodeRabbit
- **Improvements**
- Enhanced reliability of GitHub-powered content during site builds.
- GitHub API requests now use secure authentication when a token is
available, improving consistency and reducing rate-limit risk.
- Repository star and agent-skill loading continues to work gracefully
without token access.
- **Chores**
- Streamlined the type-check workflow to use a leaner content build
before running TypeScript checks.
- Passed the GitHub token through relevant CI task environments to
enable authenticated requests.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Joshen Lim
06aafe4e0a