Fixes for track management

src/provider.rs

@@ -104,6 +104,24 @@ pub trait MetadataProvider: Send + Sync {
         &self,
         release_mbid: &str,
     ) -> impl std::future::Future<Output = TagResult<Vec<ReleaseTrack>>> + Send;
+
+    /// Get deduplicated release groups (albums, EPs, singles) for an artist.
+    fn get_artist_release_groups(
+        &self,
+        artist_mbid: &str,
+    ) -> impl std::future::Future<Output = TagResult<Vec<ReleaseGroupEntry>>> + Send;
+}
+
+/// A release group (deduplicated album/EP/single concept).
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ReleaseGroupEntry {
+    pub mbid: String,
+    pub title: String,
+    pub primary_type: Option<String>,
+    pub secondary_types: Vec<String>,
+    pub first_release_date: Option<String>,
+    /// MBID of the first release in this group (for fetching tracks).
+    pub first_release_mbid: Option<String>,
 }
 
 /// A track within a release.