Preserve complete branch selectors when Git truncates or disambiguates short names, and keep slash-named local branches separate from remote-tracking refs through worktree creation and reuse.
Keep native/SSH namespace boundaries and mixed-version client capability gates intact. Accept Git-valid dotted components and cover collisions with configured and orphan tracking refs.
Adapted from @nishino-tsukasa's #19540. Independently reviewed in seven adversarial rounds; 235 focused tests and 77 affected-Apple-Git tests pass, along with typecheck, quality checks, and the desktop build.
Correct the inherited file-explorer cache-scan expectation while retaining its exact constant-work bound.
Correct the inherited release-parser compatibility assertion to match the pinned test dependency; all 121 cross-version tests pass locally.
Fixes#19515
Co-authored-by: kino <nishinotsukasavirgo@gmail.com>