Improve plugin manifest handling and UI property

Removed remarks from GetPluginManifest docs.
GetPluginManifest now returns an empty list if null.
ExternalPlugins property always enumerates and sorts plugins.
Added BOM to PublicAPIInstance.cs.

Author: Jack251970

Flow.Launcher.Plugin/Interfaces/IPublicAPI.cs

@@ -535,9 +535,6 @@ public interface IPublicAPI
         /// <summary>
         /// Get the plugin manifest.
         /// </summary>
-        /// <remarks>
-        /// If Flow cannot get manifest data, this could be null
-        /// </remarks>
         /// <returns></returns>
         public IReadOnlyList<UserPlugin> GetPluginManifest();
 

Flow.Launcher/PublicAPIInstance.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Specialized;
@@ -583,7 +583,7 @@ public ValueTask<ImageSource> LoadImageAsync(string path, bool loadFullImage = f
         public Task<bool> UpdatePluginManifestAsync(bool usePrimaryUrlOnly = false, CancellationToken token = default) =>
             PluginsManifest.UpdateManifestAsync(usePrimaryUrlOnly, token);
 
-        public IReadOnlyList<UserPlugin> GetPluginManifest() => PluginsManifest.UserPlugins;
+        public IReadOnlyList<UserPlugin> GetPluginManifest() => PluginsManifest.UserPlugins ?? [];
 
         public bool PluginModified(string id) => PluginManager.PluginModified(id);
 

Flow.Launcher/SettingPages/ViewModels/SettingsPanePluginStoreViewModel.cs

@@ -82,7 +82,7 @@ public bool ShowExecutable
         }
     }
 
-    public IList<PluginStoreItemViewModel> ExternalPlugins => App.API.GetPluginManifest()?
+    public IList<PluginStoreItemViewModel> ExternalPlugins => App.API.GetPluginManifest()
         .Select(p => new PluginStoreItemViewModel(p))
         .OrderByDescending(p => p.Category == PluginStoreItemViewModel.NewRelease)
         .ThenByDescending(p => p.Category == PluginStoreItemViewModel.RecentlyUpdated)