Nothing calls it anymore now that the commit-surgery operations run on a
worker with input blocked. Remove the helper, its bespoke synchronous
spinner loop (renderAppStatusSync/setAppStatusContent), the popup-handler
plumbing, and the interface method.
That loop was also the only thing suppressing the yellow "Rebasing" mode
indicator (and its reset button) while lazygit drives a rebase itself.
Move that suppression to WithWaitingStatusBlockingInput so it applies to
every input-blocking commit-surgery op — including the ones that already
ran on a worker (edit, drop, and so on) and previously let the indicator
flash on mid-operation. It's cleared after the refresh, so an operation
that legitimately leaves a rebase in progress still shows the mode.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>