Revert "Add is_trakt_group field to PlaylistGroup and update sorting logic"

This reverts commit 27d84edf9c.

backend/src/processing/parser/m3u.rs

@@ -266,7 +266,7 @@ where
         if let Some((cluster, group_title)) = channel.map(|pli|
             (pli.header.xtream_cluster, &pli.header.group)) {
             grp_id += 1;
-            Some(PlaylistGroup { id: grp_id, xtream_cluster: cluster, title: group_title.to_string(), channels, is_trakt_group: false })
+            Some(PlaylistGroup { id: grp_id, xtream_cluster: cluster, title: group_title.to_string(), channels })
         } else {
             None
         }

backend/src/processing/parser/xtream.rs

@@ -180,7 +180,6 @@ pub fn parse_xtream(input: &ConfigInput,
                                 xtream_cluster,
                                 title: category.category_name.to_string(),
                                 channels: category.channels.clone(),
-                                is_trakt_group: false,
                             }
                         }).collect()))
                 }