fn resolve_worktree_base(root: &Path) -> Option<PathBuf>Expand description
worktree_base without the memo; None when git could not answer.
The first entry of git worktree list --porcelain is the main working
tree: the main checkout for a linked worktree, the repo root from a
subdirectory. A repo kept in a separate git dir is not a supported
layout - git names its admin dir there, and the CLI’s base for it is
unverified - so forge follows git rather than guessing.