put the download indicator on the artist line, tight to its left

The glyph and the progress ring sat in the title row after the star, spaced 8dp;
they now lead the subtitle row, 4dp from the artist name, which is where the
artist line has room for them. `theDownloadedIndicatorSitsOnTheArtistLineToItsLeft`
measures the unmerged bounds and fails if the indicator moves back up to the
title line or to the artist's right.

app/src/main/kotlin/com/subtracks/ui/library/SongsContent.kt

@@ -89,16 +89,21 @@ fun SongRow(
                     modifier = Modifier.weight(1f, fill = false),
                 )
                 StarredBadge(song.starred != null)
-                DownloadBadge(download)
             }
         },
         supportingContent = {
-            Text(
-                text = song.artist.orEmpty().ifEmpty { "\u00A0" },
-                color = if (isPlaying) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant,
-                maxLines = 1,
-                overflow = TextOverflow.Ellipsis,
-            )
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.spacedBy(4.dp),
+            ) {
+                DownloadBadge(download)
+                Text(
+                    text = song.artist.orEmpty().ifEmpty { "\u00A0" },
+                    color = if (isPlaying) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant,
+                    maxLines = 1,
+                    overflow = TextOverflow.Ellipsis,
+                )
+            }
         },
         colors = ListItemDefaults.colors(containerColor = Color.Transparent),
     )