Fetches the latest commit object for a given branch of a package from
the GitHub API. Returns a fallback list of `NA` values on error so
callers can handle missing branches gracefully.
Usage
latest_commit_for_branch(package, branch)
Arguments
- package
Character. Core PIP package name.
- branch
Character scalar. Branch name. No default; must be
provided explicitly by internal callers.
Value
A list (the raw GitHub API response) containing at minimum:
`$sha` (the commit SHA) and `$commit$author` (with `$date` and `$name`).
On error, returns a list with `$commit$author$date` = `NA` and
`$commit$author$name` = `NA`.