/status was admin-only (404 for everyone else). Serve it to all: a
reader view with per-feed live/idle/delayed status and last-update time,
while admins additionally get poll cadence, item/story counts, paywall
rates, posting times, and raw fetch errors. Error strings are stripped
server-side for non-admins so feed-specific workarounds and upstream URLs
never reach the public payload. Nav status link now shows for everyone.