Decision (#157): the tripwire only alerted, so a symlink planted in the
Syncthing-shared brain dir stayed readable until a human removed it.
Watch now unlinks every symlink it finds through an os.Root on the brain
dir (re-checking it is still a symlink; the target is never touched),
and the default scan interval drops from 5 min to 30 s, so a planted
link is readable for at most one interval.
Each removal is an alert naming what was removed; a persistent finding
(a link it could not remove, an unreadable dir, a scan error) alerts
once per distinct state. Alerts queue until Notify succeeds, so an ntfy
outage delays them without losing them, even though the next scan of
the cleaned brain is clean.
The startup check still refuses to start on any symlink.
Refs #157
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>