Three UI fixes:
1. MapLive now ticks every 60s and, when the selected_time is still
the "Now" slot, advances to the newer latest-past-or-now hour as
the clock crosses into it. The URL is patched in place so shared
links stay accurate without polluting history. Manually picking a
specific past/future hour turns tracking off.
2. point_forecast/3 now reads its valid_times list straight from the
on-disk .ntms files (same source the main-map timeline uses), then
consults the cache per-hour for a fast score lookup. The old cache-
or-store branch could leave the click-to-detail sparkline at 13
hours while the bottom timeline showed 14+; both now line up.
3. Point-detail panel moves from bottom-14 → bottom-24 on desktop so
its lower edge clears the forecast-timeline bar (+ max-height tuned
to match), fixing the overlap visible in screenshots.
Graham McIntire
ffb14cb64f