feat: v1.30.0 — Discord RPC, offline bulk download, artist images, lazy loading, crossfade fix

- Discord Rich Presence (opt-in) — requested by @Bewenben (#49)
- Bulk offline download for playlists and artist discographies — requested by @Apollosport (#54)
- Offline Library filter tabs: All / Albums / Playlists / Discographies with artist grouping
- Artist images on Artists overview (opt-in, off by default) — reported by @Apollosport (#53)
- Image lazy loading via IntersectionObserver (300px margin) across all pages
- Fix: crossfade no longer triggers on manual track skip — reported by @netherguy4 (#35)
- Fix: playlist offline cache now stored as single entry (not per-album)
- Fix: image cache AbortController no longer blocks IDB writes
- Update toast: experimental auto-update hint + GH download link always visible (Win/Mac)
- Queue tech strip: genre removed
- Facebook theme: contrast, opaque badge/back button, queue tab labels
- "Save discography offline" label (was "Download discography")
- Fix: clearing empty playlists via updatePlaylist.view (Axios empty array workaround)
- starredOverrides propagated to AlbumDetail, Favorites, RandomMix

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/styles/components.css

@@ -723,6 +723,63 @@
   color: var(--color-error, #e05050);
 }
 
+/* Filter tabs */
+.offline-filter-tabs {
+  display: flex;
+  gap: 6px;
+  flex-wrap: wrap;
+}
+
+.offline-filter-tab {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 6px 14px;
+  border-radius: 20px;
+  border: 1px solid var(--border);
+  background: none;
+  color: var(--text-secondary);
+  font-size: 13px;
+  cursor: pointer;
+  transition: background 0.15s, color 0.15s, border-color 0.15s;
+}
+
+.offline-filter-tab:hover {
+  color: var(--text-primary);
+  border-color: var(--accent);
+}
+
+.offline-filter-tab.active {
+  background: var(--accent);
+  color: var(--ctp-base);
+  border-color: var(--accent);
+  font-weight: 600;
+}
+
+.offline-filter-tab-count {
+  font-size: 11px;
+  opacity: 0.75;
+}
+
+.offline-filter-tab.active .offline-filter-tab-count {
+  opacity: 0.85;
+}
+
+/* Artist discography groups */
+.offline-artist-group {
+  display: flex;
+  flex-direction: column;
+  gap: 12px;
+}
+
+.offline-artist-group-heading {
+  font-size: 16px;
+  font-weight: 700;
+  color: var(--text-primary);
+  padding-bottom: 6px;
+  border-bottom: 1px solid var(--border);
+}
+
 .album-detail {
   display: flex;
   flex-direction: column;
@@ -1496,6 +1553,70 @@
   min-height: unset;
 }
 
+/* ── Random Mix — clickable artist name ── */
+.rm-artist-btn {
+  background: none;
+  border: none;
+  padding: 0;
+  margin: 0;
+  font-size: 12px;
+  color: var(--text-secondary);
+  cursor: pointer;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  max-width: 100%;
+  text-align: left;
+  text-decoration: underline;
+  text-decoration-style: dotted;
+  text-decoration-color: transparent;
+  transition: color 0.15s, text-decoration-color 0.15s;
+}
+.rm-artist-btn:hover {
+  color: var(--accent);
+  text-decoration-color: var(--accent);
+}
+.rm-artist-btn.is-blocked {
+  color: var(--danger);
+  text-decoration-color: var(--danger);
+  cursor: default;
+}
+.rm-artist-btn.just-added {
+  color: var(--accent);
+  text-decoration-color: var(--accent);
+}
+
+/* ── Random Mix — genre pill chip ── */
+.rm-genre-chip {
+  display: inline-block;
+  background: var(--bg-hover);
+  border: none;
+  border-radius: var(--radius-sm);
+  padding: 2px 8px;
+  font-size: 11px;
+  font-weight: 500;
+  color: var(--text-muted);
+  cursor: pointer;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  max-width: 100%;
+  transition: background 0.15s, color 0.15s;
+}
+.rm-genre-chip:hover {
+  background: color-mix(in srgb, var(--accent) 20%, transparent);
+  color: var(--accent);
+}
+.rm-genre-chip.is-blocked {
+  background: color-mix(in srgb, var(--danger) 15%, transparent);
+  color: var(--danger);
+  cursor: default;
+}
+.rm-genre-chip.just-added {
+  background: color-mix(in srgb, var(--accent) 20%, transparent);
+  color: var(--accent);
+}
+
 /* ─ Modal ─ */
 .modal-overlay {
   position: fixed;