feat: add NuGet and Godot distribution

DotNet~/Runtime/ShrinkContextAppHost.cs

@@ -0,0 +1,31 @@
+#nullable enable
+
+using System;
+using System.Collections.Generic;
+using Cysharp.Threading.Tasks;
+using ShrinkApp;
+
+namespace ShrinkContext.AppAdapter;
+
+public sealed class ShrinkContextAppHost
+{
+    private readonly ShrinkContextRuntime _runtime = new();
+    private readonly ShrinkComponentCatalog _catalog = new();
+    private readonly ShrinkContextLoader _loader;
+
+    public ShrinkContextAppHost(ShrinkAppServices? services = null)
+    {
+        Services = services ?? new ShrinkAppServices();
+        _loader = new ShrinkContextLoader(_runtime, _catalog);
+    }
+
+    public ShrinkAppServices Services { get; }
+    public ShrinkContextRuntime Runtime => _runtime;
+    public ShrinkLoaderTransactionDiagnostic? LastTransaction => _loader.LastTransaction;
+
+    public void Register(string name, Func<IShrinkComponent> factory) => _catalog.Register(name, factory);
+    public void Register<TComponent>(string name) where TComponent : IShrinkComponent, new() =>
+        _catalog.Register<TComponent>(name);
+    public UniTask ApplyAsync(IReadOnlyList<ShrinkLoaderEntry> entries) => _loader.ApplyAsync(entries);
+    public UniTask ShutdownAsync() => _runtime.ShutdownAsync();
+}