Added direct-chat launchers for assistant plugins and a dialog to reconfigure them (#935)

Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/MindWork AI Studio/Program.cs

@@ -180,6 +180,7 @@ internal sealed class Program
         builder.Services.AddSingleton<UpdatePolicy>();
         builder.Services.AddSingleton<AssistantPluginGenerationService>();
         builder.Services.AddSingleton<DataSourceService>();
+        builder.Services.AddSingleton<DirectChatService>();
         builder.Services.AddScoped<PandocAvailabilityService>();
         builder.Services.AddTransient<HTMLParser>();
         builder.Services.AddTransient<AgentDataSourceSelection>();