Comments on plays

- Anyone who can see a play can read its comments; the player and the people they follow can write.
  The author, the player and admins can delete; comments can be reported (admins see the text).
- Notifications: "commented on" for the player, "replied on" for earlier commenters, each with its
  own setting. Reaction and comment notifications now open the play.
- A 💬 chip with the count next to reactions on the feed and recent plays, opening the thread on
  the app (/play/[id]) and the website. Threads refresh every few seconds while open.
- Blocking removes comments between the two people. Plays with comments survive history trimming.
- Privacy page updated.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011Y2iUsKEWDuRGjK5FPmcUP

apps/mobile/src/components/NowPlayingCard.tsx

@@ -101,7 +101,7 @@ export function NowPlayingCard({
         <TrackRow track={np.track} preferred={preferred} expanded={expanded} onToggle={toggle} />
       </Animated.View>
       <ProgressBar np={np} compact={!expanded} />
-      <Reactions listenId={np.listenId} reactions={np.reactions} ownerId={np.user.id} />
+      <Reactions listenId={np.listenId} reactions={np.reactions} ownerId={np.user.id} commentCount={np.commentCount ?? 0} />
       {expanded && (
         <Animated.View entering={FadeIn.duration(200)} exiting={FadeOut.duration(120)} style={styles.details}>
           <ServiceLinks track={np.track} preferred={preferred} />