feat(library): genre sliders, artist links, and navigation utils

- music landing: diverse per-genre album sliders (online counts /
  offline wide-probe fallback) and home-screen library shortcuts
- add ArtistLinks component and shared navigation/genreDiversity utils
- player/playback-mode refinements across Rust and frontend

src/routes/library/+layout.svelte

@@ -7,6 +7,7 @@
   import { auth, isAuthenticated, isLoading as isAuthLoading, currentUser } from "$lib/stores/auth";
   import { library } from "$lib/stores/library";
   import { currentMedia, isPlaying, playbackPosition, playbackDuration, shouldShowAudioMiniPlayer } from "$lib/stores/player";
+  import { isShuffle, repeatMode, hasNext as hasNextStore, hasPrevious as hasPreviousStore } from "$lib/stores/queue";
   import { useScrollGuard } from "$lib/composables/useScrollGuard";
   import Search from "$lib/components/Search.svelte";
   import MiniPlayer from "$lib/components/player/MiniPlayer.svelte";
@@ -23,16 +24,15 @@
   let showFullPlayer = $state(false);
   let showOverflowMenu = $state(false);
   let showSleepTimerModal = $state(false);
-  let shuffle = $state(false);
-  let repeat = $state<"off" | "all" | "one">("off");
-  let hasNext = $state(false);
-  let hasPrevious = $state(false);
+  // Queue status (shuffle, repeat, hasNext, hasPrevious) is event-driven via the
+  // queue store, which listens for queue_changed events from the backend. This
+  // updates instantly when toggling shuffle/repeat (no polling lag).
+  const shuffle = $derived($isShuffle);
+  const repeat = $derived($repeatMode);
+  const hasNext = $derived($hasNextStore);
+  const hasPrevious = $derived($hasPreviousStore);
   let isAndroid = $state(false);
 
-  let pollInterval: ReturnType<typeof setInterval> | null = null;
-  let failedAttempts = 0;
-  const MAX_SILENT_FAILURES = 3; // Don't log errors for first 3 attempts
-
   onMount(() => {
     // Detect platform
     try {
@@ -42,17 +42,7 @@
       console.error("Platform detection failed:", err);
     }
 
-    // Poll for queue status (shuffle, repeat, hasNext, hasPrevious)
-    // Position/duration come from player events (pushed every 250ms)
-    // Add a small delay before starting polling to ensure player is ready on Android
-    const timeoutId = setTimeout(() => {
-      updateQueueStatus(); // Initial update
-      pollInterval = setInterval(updateQueueStatus, 1000);
-    }, 100);
-
     return () => {
-      clearTimeout(timeoutId);
-      if (pollInterval) clearInterval(pollInterval);
       scrollGuard.cleanup();
     };
   });
@@ -64,26 +54,6 @@
     }
   });
 
-  async function updateQueueStatus() {
-    try {
-      const queue = await commands.playerGetQueue();
-
-      // Reset failure counter on success
-      failedAttempts = 0;
-
-      hasNext = queue.hasNext;
-      hasPrevious = queue.hasPrevious;
-      shuffle = queue.shuffle;
-      repeat = queue.repeat as "off" | "all" | "one";
-    } catch (e) {
-      failedAttempts++;
-      // Only log errors after initial attempts (player may still be initializing)
-      if (failedAttempts > MAX_SILENT_FAILURES) {
-        console.error("[Queue Status] Error:", e);
-      }
-    }
-  }
-
   async function handleLogout() {
     await auth.logout();
     library.reset();