feat: replace dot with left border line on park rows/cards

Open parks get a colored left border (green/amber/blue) instead of a dot.
Region headers lose their accent line; distinguished by "— REGION —" format
with higher-contrast text instead.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/ParkCard.tsx

@@ -31,6 +31,9 @@ export function ParkCard({ park, weekDates, parkData, today, openRideCount, coas
       <div className="park-card" style={{
         background: "var(--color-surface)",
         border: "1px solid var(--color-border)",
+        borderLeft: isOpen
+          ? `3px solid ${isWeatherDelay ? "var(--color-weather-border)" : isClosing ? "var(--color-closing-border)" : "var(--color-open-border)"}`
+          : "1px solid var(--color-border)",
         borderRadius: 12,
         overflow: "hidden",
       }}>