Fix JSONID type conversions for yandex-music-api-go v0.0.0-20261018072517-d0173f795d2a

The new library version uses models.JSONID (custom string type) for ID
fields instead of plain string. Convert to string where IDs are passed
to functions expecting string or compared with string values.

Affected: client.go (GetTrackInfoWithPosition), downloader.go
(track.ID usage), monitor.go (track.ID, album.ID usage), storage.go
(album/track ID assignment).

internal/yandex/client.go

@@ -123,14 +123,14 @@ func (c *YandexClient) GetTrackInfoWithPosition(ctx context.Context, trackID str
 	// Extract track position from first album
 	var position *TrackPosition
 	if len(track.Albums) > 0 {
-		albumID := track.Albums[0].ID
+		albumID := string(track.Albums[0].ID)
 		albums, err := c.client.GetAlbumsWithTracks(ctx, []string{albumID})
 		if err == nil && len(albums) > 0 {
 			album := albums[0]
 			// Find track in album.Volumes and get position
 			for volIdx, volume := range album.Volumes {
 				for trackIdx, t := range volume {
-					if t.ID == trackID {
+					if string(t.ID) == trackID {
 						position = &TrackPosition{
 							Volume: volIdx + 1,
 							Index:  trackIdx + 1,