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();
+}

DotNet~/ShrinkSDK.Context.AppAdapter.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFramework>netstandard2.1</TargetFramework>
+    <EnableDefaultCompileItems>false</EnableDefaultCompileItems>
+    <AssemblyName>ShrinkContext.AppAdapter</AssemblyName>
+    <RootNamespace>ShrinkContext.AppAdapter</RootNamespace>
+    <PackageId>ShrinkSDK.Context.AppAdapter</PackageId>
+    <Version>0.2.0</Version>
+    <Description>Engine-neutral ShrinkContext composition host for ShrinkApp.</Description>
+    <ShrinkCodeGenEnabled>false</ShrinkCodeGenEnabled>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="Runtime\*.cs" />
+    <PackageReference Include="ShrinkSDK.Context.Core" Version="0.2.0" />
+    <PackageReference Include="ShrinkSDK.App.Core" Version="0.2.0" />
+  </ItemGroup>
+</Project>