fix: unmarshal LB top recordings from snake_case wire format, cap at 10

The ListenBrainz popularity API returns snake_case JSON fields
(recording_name, artist_name, total_listen_count, recording_mbid)
but LBTopRecording used camelCase JSON tags for Wails serialization.
All fields silently deserialized as zero values — empty strings and
zero counts — producing ~8000 blank rows in the top tracks section.

Fix: add lbTopRecordingWire with snake_case tags for API unmarshal,
convert to LBTopRecording (camelCase) for Wails. Cap results at 10
to avoid rendering thousands of rows for prolific artists.

backend/explore/listenbrainz.go

@@ -68,12 +68,25 @@ func (c *ListenBrainzClient) TopRecordingsForArtist(
 		return nil, fmt.Errorf("listenbrainz top recordings: %w", err)
 	}
 
-	// The API returns an array directly.
-	var out []LBTopRecording
-	if err := json.Unmarshal(body, &out); err != nil {
+	// The API returns snake_case JSON — unmarshal into wire type,
+	// then convert to the camelCase Wails type.
+	var wire []lbTopRecordingWire
+	if err := json.Unmarshal(body, &wire); err != nil {
 		return nil, fmt.Errorf("listenbrainz top recordings unmarshal: %w", err)
 	}
 
+	const maxTopRecordings = 10
+
+	limit := len(wire)
+	if limit > maxTopRecordings {
+		limit = maxTopRecordings
+	}
+
+	out := make([]LBTopRecording, limit)
+	for i := range limit {
+		out[i] = wire[i].toPublic()
+	}
+
 	c.cacheJSON(cacheKey, out, cacheTTLSearch, artistMBID, "artist")
 
 	return out, nil

backend/explore/types.go

@@ -68,6 +68,10 @@ type MBTrack struct {
 
 // LBTopRecording represents a popular recording from the
 // ListenBrainz popularity API.
+//
+// JSON tags use camelCase for Wails→frontend serialization.
+// The API response uses snake_case, so we unmarshal into
+// lbTopRecordingWire first, then convert.
 type LBTopRecording struct {
 	RecordingMBID    string `json:"recordingMbid"`
 	ArtistName       string `json:"artistName"`
@@ -75,6 +79,25 @@ type LBTopRecording struct {
 	TotalListenCount int    `json:"totalListenCount"`
 }
 
+// lbTopRecordingWire matches the ListenBrainz API's snake_case
+// JSON response for the popularity/top-recordings-for-artist
+// endpoint.
+type lbTopRecordingWire struct {
+	RecordingMBID    string `json:"recording_mbid"`
+	ArtistName       string `json:"artist_name"`
+	RecordingName    string `json:"recording_name"`
+	TotalListenCount int    `json:"total_listen_count"`
+}
+
+func (w lbTopRecordingWire) toPublic() LBTopRecording {
+	return LBTopRecording{
+		RecordingMBID:    w.RecordingMBID,
+		ArtistName:       w.ArtistName,
+		TrackName:        w.RecordingName,
+		TotalListenCount: w.TotalListenCount,
+	}
+}
+
 // LBSimilarArtist represents a similar artist from the
 // ListenBrainz labs API.
 type LBSimilarArtist struct {