feat: add personal playlists and shareable track links

EOF

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/mobile/src/ui/kit.tsx

@@ -1,4 +1,5 @@
 import MaterialIcons from '@expo/vector-icons/MaterialIcons';
+import { useRouter } from 'expo-router';
 import { ApiError, type Track } from '@pipu/core';
 import type { ComponentProps, ReactNode } from 'react';
 import { useState, useSyncExternalStore } from 'react';
@@ -199,6 +200,7 @@ export function TrackRow({
   const colors = useColors();
   const { t } = useTranslation();
   const liked = track.reaction === 'like';
+  const router = useRouter();
   const saved = useSyncExternalStore(downloads.subscribe, () => downloads.isDownloaded(track.id));
   return (
     <Pressable
@@ -233,6 +235,10 @@ export function TrackRow({
         </Pressable>
       )}
       {trailing}
+      <Pressable accessibilityRole="button" accessibilityLabel={t('playlists.add')} style={{ padding: 8 }}
+        onPress={(e) => { e.stopPropagation(); router.push({ pathname: '/playlists', params: { track: track.id } }); }}>
+        <Icon name="playlist-add" size={22} />
+      </Pressable>
       {saved && !trailing && <Icon name="download-done" size={16} color={colors.accent2} />}
       <Text style={s.duration}>{formatDuration(track.duration_ms)}</Text>
     </Pressable>