FAIL

- apps/ely-tree/src/git.rs:86 — `born()` accepts an absent symbolic reference outside `refs/heads/` as an unborn branch, still hiding real Git errors (rule 2). Reproduction on native Windows and WSL Linux: initialize a repository, then run `git symbolic-ref HEAD refs/tags/missing`. `rev-parse --verify -q HEAD` exits 1, `symbolic-ref -q HEAD` succeeds, and `for-each-ref` finds nothing; `born()` returns `Ok(false)` and both reflog and LFS return `Ok([])`, although `git reflog show HEAD --` fails with `fatal: bad revision 'HEAD'`. Require the resolved symbolic target to be a branch under `refs/heads/` before accepting it as unborn; otherwise surface Git's diagnostic, and add a regression for this case. Evidence: `.work/G-03-r2/windows-probe.log`, `.work/G-03-r2/linux-probe.log`.