Fetch and prune the preferred remote, then reconcile every local branch
independently. Fast-forward branches that are behind, preserve divergent work,
and delete a branch only when its configured upstream is gone and its commits
are already contained by the remote default branch.
Keep dirty repositories eligible while protecting the active branch and refs
checked out in linked worktrees. Preserve the previous all-clean policy behind
--strict, expose structured per-branch results, add real bare-remote integration
tests, and retain the upstream MIT notice for the adapted hub sync behavior.
