feat: add album favorites in header and unify browse controls

Improve album workflow with in-header favorite toggle, keep favorite state synced from backend, and normalize browse top-bar sizing while increasing audio output buffer headroom to reduce glitches.

src/view/maincontent.cpp

@@ -48,6 +48,13 @@ MainContent::MainContent(QobuzBackend *backend, PlayQueue *queue, QWidget *paren
             return;
         emit playlistFollowToggled(id, !m_header->playlistFollowed());
     });
+    QObject::connect(m_header->favButton(), &QPushButton::clicked,
+                     [this] {
+        const QString albumId = m_header->albumId();
+        if (albumId.isEmpty())
+            return;
+        emit albumFavoriteToggled(albumId, !m_header->albumFaved());
+    });
 
     m_albumList  = new AlbumListView(this);
     m_artistList = new ArtistListView(this);
@@ -77,7 +84,10 @@ void MainContent::showWelcome()       { m_stack->setCurrentIndex(0); }
 
 void MainContent::showAlbum(const QJsonObject &album)
 {
-    m_header->setAlbum(album);
+    QString albumId = album["id"].toString();
+    if (albumId.isEmpty() && album["id"].isDouble())
+        albumId = QString::number(static_cast<qint64>(album["id"].toDouble()));
+    m_header->setAlbum(album, m_favAlbumIds.contains(albumId));
     m_tracks->loadAlbum(album);
     m_stack->setCurrentIndex(1);
 }
@@ -131,6 +141,14 @@ void MainContent::setFavArtistIds(const QSet<qint64> &ids)
     m_artistView->setFavArtistIds(ids);
 }
 
+void MainContent::setFavAlbumIds(const QSet<QString> &ids)
+{
+    m_favAlbumIds = ids;
+    const QString shownAlbumId = m_header->albumId();
+    if (!shownAlbumId.isEmpty())
+        m_header->setAlbumFaved(m_favAlbumIds.contains(shownAlbumId));
+}
+
 void MainContent::onDeepShuffleTracks(const QJsonArray &tracks)
 {
     if (m_genreBrowser->tryHandleDeepShuffleTracks(tracks))