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Created by pull[bot] (v2.0.0-alpha.4)

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Summary by cubic

Enables installing private GitHub CLI extensions in the github-cli feature. Previously installs only worked reliably for public repos; now installs clone via git with the gh credential helper and forward tokens to the non-root user.

• Whitelists GH_TOKEN/GITHUB_TOKEN through su --login during extension installs.
• Clones with git -c credential.helper='!gh auth git-credential' to authenticate to private repos.
• Checks for a real gh by isolating GH_CONFIG_DIR and unsetting tokens before deciding to install a wrapper.
• Updates docs and bumps feature version to 1.1.1.

Using private extensions

• Set the extensions option to a comma-separated list of repos (for example, owner/repo).
• Provide GH_TOKEN or GITHUB_TOKEN with access to those repos at feature installation time.

^{Written for commit 8b03a98. Summary will update on new commits.}