feat: show both Celsius and Fahrenheit in weather widget

src/components/WeatherWidget.tsx

@@ -2,6 +2,10 @@
 
 import { useState, useEffect } from 'react';
 
+function celsiusToFahrenheit(c: number): number {
+  return Math.round((c * 9/5) + 32);
+}
+
 export default function WeatherWidget() {
   const [weather, setWeather] = useState<any>(null);
   const [loading, setLoading] = useState(true);
@@ -63,6 +67,9 @@ export default function WeatherWidget() {
   };
 
   const icon = weatherIcons[current.weathercode] || '🌤️';
+  const tempF = celsiusToFahrenheit(current.celsius);
+  const maxF = celsiusToFahrenheit(today.maxC);
+  const minF = celsiusToFahrenheit(today.minC);
 
   return (
     <div style={{ 
@@ -77,8 +84,8 @@ export default function WeatherWidget() {
       <div style={{ display: 'flex', alignItems: 'center', gap: '10px' }}>
         <span style={{ fontSize: '28px' }}>{icon}</span>
         <div>
-          <div style={{ fontSize: '22px', fontWeight: '600', color: '#1a1a2e' }}>
-            {current.celsius}°C
+          <div style={{ fontSize: '18px', fontWeight: '600', color: '#1a1a2e' }}>
+            {current.celsius}°C / {tempF}°F
           </div>
           <div style={{ fontSize: '11px', color: '#666', marginTop: '2px' }}>
             {current.summary}
@@ -95,7 +102,7 @@ export default function WeatherWidget() {
         color: '#555'
       }}>
         <span>📍 Otavalo</span>
-        <span>↑{today.maxC}° ↓{today.minC}°</span>
+        <span>↑{today.maxC}°C ({maxF}°F) ↓{today.minC}°C ({minF}°F)</span>
       </div>
     </div>
   );