Improved handling of moonlight plugins during startup, minimized host project code and moved startup handling to core

Moonlight.Api/MoonlightPlugin.cs

@@ -0,0 +1,28 @@
+using System.Reflection;
+using System.Text.Json.Serialization;
+using Microsoft.AspNetCore.Builder;
+using SimplePlugin.Abstractions;
+
+namespace Moonlight.Api;
+
+public abstract class MoonlightPlugin : IPluginModule
+{
+    protected MoonlightPlugin[] Plugins { get; private set; }
+
+    public void Initialize(MoonlightPlugin[] plugins)
+    {
+        Plugins = plugins;
+    }
+    
+    public virtual void PreBuild(WebApplicationBuilder builder)
+    {
+    }
+
+    public virtual void PostBuild(WebApplication application)
+    {
+    }
+
+    public virtual void PostMiddleware(WebApplication application)
+    {
+    }
+}