unreal_mod_manager: allow loading mods with unknown DownloadMode

unreal_mod_manager/src/app.rs

@@ -445,7 +445,7 @@ impl ModLoaderApp {
             .show_ui(ui, |ui| {
                 // for when there is an Index file show force latest version, this to diecrtly indicate that there
                 // is the possibility of an auto update vie an index file.
-                if game_mod.download.is_some() {
+                if game_mod.download.is_some() && game_mod.download.as_ref().unwrap().download_mode == unreal_mod_metadata::DownloadMode::IndexFile {
                     let latest_version = game_mod.latest_version.clone().unwrap();
                     ui.selectable_value(
                         &mut game_mod.selected_version,

unreal_mod_manager/src/mod_processing/index_file.rs

@@ -91,7 +91,7 @@ pub(crate) fn gather_index_files(
 
     data.game_mods
         .iter()
-        .filter(|(mod_id, _)| filter.contains(mod_id))
+        .filter(|(mod_id, game_mod)| filter.contains(mod_id) && game_mod.download.is_some() && game_mod.download.as_ref().unwrap().download_mode == unreal_mod_metadata::DownloadMode::IndexFile)
         .filter_map(|(mod_id, game_mod)| {
             game_mod
                 .download

unreal_mod_metadata/src/lib.rs

@@ -51,12 +51,15 @@ impl std::fmt::Display for SyncMode {
 pub enum DownloadMode {
     #[serde(rename = "index_file")]
     IndexFile,
+    #[serde(other)]
+    Unknown,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Hash)]
 pub struct DownloadInfo {
     #[serde(rename = "type")]
     pub download_mode: DownloadMode,
+    #[serde(default)]
     pub url: String,
 }