feat: add playlist browse/search discovery and follow controls

src/list/library.cpp

@@ -21,6 +21,7 @@ enum NodeType {
     NodeFavArtists,
     NodePlaylist,
     NodeBrowseGenres,
+    NodeBrowsePlaylists,
 };
 
 Library::Library(QobuzBackend *backend, QWidget *parent)
@@ -79,6 +80,9 @@ void Library::buildStaticNodes()
 
     auto *genresItem = new QTreeWidgetItem(m_browseNode, QStringList{tr("Genres")});
     genresItem->setData(0, TypeRole, NodeBrowseGenres);
+
+    auto *playlistsItem = new QTreeWidgetItem(m_browseNode, QStringList{tr("Playlists")});
+    playlistsItem->setData(0, TypeRole, NodeBrowsePlaylists);
 }
 
 void Library::refresh()
@@ -176,6 +180,7 @@ void Library::onItemClicked(QTreeWidgetItem *item, int)
     case NodeFavAlbums:  emit favAlbumsRequested();  break;
     case NodeFavArtists: emit favArtistsRequested(); break;
     case NodeBrowseGenres: emit browseGenresRequested(); break;
+    case NodeBrowsePlaylists: emit browsePlaylistsRequested(); break;
     case NodePlaylist: {
         const qint64  id   = item->data(0, IdRole).toLongLong();
         const QString name = item->data(0, NameRole).toString();

src/list/library.hpp

@@ -27,6 +27,7 @@ namespace List
         void favAlbumsRequested();
         void favArtistsRequested();
         void browseGenresRequested();
+        void browsePlaylistsRequested();
         void playlistRequested(qint64 playlistId, const QString &name);
         /// Emitted after playlists are loaded so others can cache the list.
         void userPlaylistsChanged(const QVector<QPair<qint64, QString>> &playlists);