Add phone playback reporting and pause sharing to the API

Phones that read system media sessions report playback themselves:
- POST /me/devices issues a per-phone token that can only call
  POST /devices/now-playing; revocable, hashed at rest, 10 per user
- Reports name the app ("via Spotify"); unknown apps use the OS label
- Push-reported playback expires after 9 minutes of silence, since
  phones send a heartbeat every 4 minutes while playing

Users can pause sharing (PUT /me/sharing: 1h, 8h, indefinitely). While
paused, connections aren't polled, phone reports are dropped, nothing is
added to history, and the current track switches to "played … ago".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MzFywujuH9TiuXbr9vjoX8

apps/api/src/services/connections.ts

@@ -50,3 +50,11 @@ export async function watchUsers(userIds: string[]) {
     );
   await pollSoon(rows.map((r) => r.id));
 }
+
+export async function connectionIdsForUser(userId: string): Promise<string[]> {
+  const rows = await db
+    .select({ id: schema.connections.id })
+    .from(schema.connections)
+    .where(and(eq(schema.connections.userId, userId), eq(schema.connections.status, 'active')));
+  return rows.map((r) => r.id);
+}

apps/api/src/services/nowPlaying.ts

@@ -14,6 +14,10 @@ export const toUserSummary = (u: Pick<User, 'id' | 'username' | 'displayName' |
   avatarUrl: u.avatarUrl,
 });
 
+/** Phones report changes and a heartbeat every few minutes; if they go quiet (app killed, no signal), stop showing "listening now". */
+export const DEVICE_STALE_MS = 9 * 60_000;
+const PUSH_SOURCES = new Set<NowPlayingProvider>(['android_media_session']);
+
 export async function getNowPlaying(userIds: string[]): Promise<NowPlayingDTO[]> {
   if (userIds.length === 0) return [];
   const rows = await db
@@ -26,8 +30,9 @@ export async function getNowPlaying(userIds: string[]): Promise<NowPlayingDTO[]>
     .map(({ np, user }) => ({
       user: toUserSummary(user),
       track: tracks.get(np.trackId)!,
-      isPlaying: np.isPlaying,
+      isPlaying: np.isPlaying && !(PUSH_SOURCES.has(np.source) && Date.now() - np.updatedAt.getTime() > DEVICE_STALE_MS),
       source: np.source,
+      sourceApp: np.sourceApp,
       progressMs: np.progressMs,
       updatedAt: np.updatedAt.toISOString(),
     }))
@@ -68,6 +73,19 @@ export async function getRecentPlays(userId: string, limit = 10): Promise<Recent
   return plays.map((p) => ({ track: tracks.get(p.trackId)!, source: p.source, playedAt: p.startedAt.toISOString() }));
 }
 
+export const isSharingPaused = (user: Pick<User, 'sharingPausedUntil'>) =>
+  Boolean(user.sharingPausedUntil && user.sharingPausedUntil > new Date());
+
+/** Starting a pause: whatever was playing becomes "played … ago" for friends. */
+export async function pauseSharing(userId: string) {
+  const updated = await db
+    .update(schema.nowPlaying)
+    .set({ isPlaying: false, updatedAt: new Date() })
+    .where(and(eq(schema.nowPlaying.userId, userId), eq(schema.nowPlaying.isPlaying, true)))
+    .returning({ userId: schema.nowPlaying.userId });
+  if (updated.length) await publishNowPlaying(userId);
+}
+
 export async function publishNowPlaying(userId: string) {
   const [dto] = await getNowPlaying([userId]);
   if (dto) await redis.publish(nowPlayingChannel(userId), JSON.stringify(dto));
@@ -78,6 +96,7 @@ export async function applyPollResult(
   userId: string,
   source: NowPlayingProvider,
   result: PollResult | null,
+  opts: { sourceApp?: string | null } = {},
 ): Promise<boolean> {
   const [current] = await db.select().from(schema.nowPlaying).where(eq(schema.nowPlaying.userId, userId));
   const now = new Date();
@@ -102,6 +121,7 @@ export async function applyPollResult(
   const values = {
     trackId: track.id,
     source,
+    sourceApp: opts.sourceApp ?? null,
     isPlaying: true,
     progressMs: result.progressMs,
     updatedAt: now,