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/lib/components/library/ArtistLinks.svelte

@@ -0,0 +1,54 @@
+<script lang="ts">
+  import { goto } from "$app/navigation";
+  import type { ArtistItem } from "$lib/api/types";
+
+  /**
+   * Renders a comma-separated list of artist names. When the artists carry
+   * ids (artistItems) each name links to that artist's detail page; otherwise
+   * it falls back to plain text from the names-only `artists` array.
+   *
+   * Consolidates the artist-linking markup used on the player and detail
+   * screens so every surface behaves the same way.
+   */
+  interface Props {
+    artistItems?: ArtistItem[] | null;
+    artists?: string[] | null;
+    /** Tailwind classes for the link colour/state. */
+    linkClass?: string;
+    /** Tailwind classes for the non-linkable fallback text. */
+    textClass?: string;
+    /** Called before navigating (e.g. to close a full-screen player). */
+    onNavigate?: () => void;
+  }
+
+  let {
+    artistItems = null,
+    artists = null,
+    linkClass = "text-[var(--color-jellyfin)] hover:underline",
+    textClass = "text-gray-400",
+    onNavigate,
+  }: Props = $props();
+
+  const linkable = $derived(
+    (artistItems ?? []).filter((a) => a.id && a.id.trim() !== "")
+  );
+
+  function handleClick(artistId: string, e: MouseEvent) {
+    e.preventDefault();
+    e.stopPropagation();
+    onNavigate?.();
+    goto(`/library/${artistId}`);
+  }
+</script>
+
+{#if linkable.length > 0}
+  <span class="inline-flex flex-wrap items-baseline gap-1">
+    {#each linkable as artist, i (artist.id)}
+      <button onclick={(e) => handleClick(artist.id, e)} class={linkClass}>
+        {artist.name}
+      </button>{#if i < linkable.length - 1}<span class={textClass}>,</span>{/if}
+    {/each}
+  </span>
+{:else if artists && artists.length > 0}
+  <span class={textClass}>{artists.join(", ")}</span>
+{/if}