queryFileContent threw on octokit errors (stale SHA 404, expired token,
network blip) and the rejection bubbled up unhandled through pullLatest
and onBadgeClick, leaving the badge stuck on "Outdated" with no log or
toast. Wrap the octokit call, log on failure, clear the cached SHA so
the next click re-resolves it, and show an error toast.
Also fix a dead `if (!user || !repo) { null }` that did nothing.
The 2-minute timer + tick ref decayed verified to stale-known and rendered
a clock icon, but the user can always click the badge to re-check. Removing
the timer simplifies the hook and the badge has one fewer visual state.
Adds a Tabler-icon badge in the stacked-note action bar showing whether
the loaded copy still matches GitHub HEAD (verified / outdated / offline
/ checking / unknown / stale-known). The save flow now re-checks before
the PUT and opens a conflict modal when GitHub has moved on, with three
explicit choices: discard local edits and pull, overwrite anyway, or
cancel. Race-condition 409s from the PUT itself are routed through the
same modal.
