RebaseOthersAfterMergeAsync now broadcasts a "rebasing" phase with i/n over the
WaitingForReview branches it checks, so the merge/continue_merge callers stop
showing the stalled "Merging…" phase while the best-effort rebase loop runs
(rebase still runs before the verify gate; a failed rebase still leaves the
merge itself successful). WorktreeMaintenanceService gained an optional
HubBroadcaster to report the same i/n shape per worktree during
cleanup/reset, with no new UI surface (deliberately out of scope). Both
review-action viewmodels now also listen on OperationProgressEvent (which
carries the total that the elapsed-seconds-only MergeProgressEvent drops) to
render "Rebasing other worktrees… (i/n)".
mika kuns
42de97e16a