android: rich GPS notification with pace, request POST_NOTIFICATIONS

- Notification title: "Bocken — Tracking GPS for active Workout"
- Live updates with elapsed time, distance, and pace (min/km)
- Request POST_NOTIFICATIONS permission at runtime (Android 13+)
- Page titles: "- Fitness" → "- Bocken" (missed in prior commit)

src/routes/fitness/[stats=fitnessStats]/+page.svelte

@@ -125,7 +125,7 @@
 
 </script>
 
-<svelte:head><title>{t('stats_title', lang)} - Fitness</title></svelte:head>
+<svelte:head><title>{t('stats_title', lang)} - Bocken</title></svelte:head>
 
 <div class="stats-page">
 	<h1>{t('stats_title', lang)}</h1>