Now panel: show day's high + its feels-like, and peak rain chance with time

Was showing right-now's temp/feels-like/rain% under a headline that's
already a whole-day summary -- mismatched framing (a day-level
headline next to point-in-time numbers).

- Big temp is now today's forecast high, with a small 'High' label.
- Feels-like is paired with that same high-temp hour, not right now.
- Rain% is the day's peak chance, shown as 'X% chance of rain around
  HH:00' instead of the current hour's (often much lower) number.

summarizeToday() now returns highTemp/highFeelsLike/rainChance
alongside the existing headline/note/umbrella, computed from the same
already-fetched hourly points. Frontend falls back to currentPoint's
own values only if summary is unexpectedly null.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

backend/src/lib/summary.js

@@ -31,8 +31,17 @@ export function summarizeToday(points, nowHour) {
   // replaces) — an hour's icon can be non-rain while it still carries a real, if
   // slim, numeric chance. Worth surfacing in the headline rather than a flat "Dry"
   // that silently disagrees with a "5%" sitting right there on an hour card.
-  const precipValues = points.map(p => p.precip_prob).filter(v => v != null)
-  const maxPrecip = precipValues.length ? Math.max(...precipValues) : null
+  // Keep the whole peak point, not just the number, so the "now" panel can show
+  // *when* that peak chance falls ("30% chance of rain around 15:00") rather
+  // than whatever the current hour's own (possibly much lower) number is.
+  const rainPeakPoint = points.reduce((best, p) =>
+    p.precip_prob != null && (!best || p.precip_prob > best.precip_prob) ? p : best, null)
+  const maxPrecip = rainPeakPoint?.precip_prob ?? null
+
+  // Day's high, and the feels-like *for that same hour* — pairing "feels like"
+  // with the temp it actually describes, rather than the current hour's feels
+  // like sitting next to a headline high from a different time of day.
+  const highPoint = points.reduce((max, p) => (p.temp_c > max.temp_c ? p : max), points[0])
 
   const laterPoints = points.filter(p => hourOf(p) >= nowHour)
   const earlierPoints = points.filter(p => hourOf(p) < nowHour)
@@ -67,7 +76,14 @@ export function summarizeToday(points, nowHour) {
   // Umbrella nudge: real rain chance either right now or coming up later today.
   const umbrella = laterWetFraction > 0.25 || rainFraction > 0.25
 
-  return { headline, note, umbrella }
+  return {
+    headline,
+    note,
+    umbrella,
+    highTemp: highPoint.temp_c,
+    highFeelsLike: highPoint.feels_like_c,
+    rainChance: rainPeakPoint ? { prob: rainPeakPoint.precip_prob, ts: rainPeakPoint.ts } : null,
+  }
 }
 
 function hourOf(point) {