feat: 公开宿主组合加载 API、Forge 风格依赖版本区间与加载顺序、程序集解析策略

- ShrinkModComponentDiscovery.Discover 公开：只发现、不执行生命周期
- ShrinkModLoader.LoadComposed / ShrinkModCordisRuntime.ApplyComposedAsync：宿主提供元数据组合加载，支持纯数据包与 IShrinkModWrapper 公开真实实例
- 公开 TryAttachEventBusInstance，随生命周期逆操作释放
- 依赖新增 VersionRange（Maven/Forge 区间语法）与 Ordering（Before/After）
- AssemblyResolvePolicy 可限制跨模组程序集解析

Runtime/Loading/ShrinkExternalModAssemblyLoader.cs

@@ -295,7 +295,7 @@ namespace ShrinkModFramework
             }
         }
 
-        private static Assembly OnAssemblyResolve(object sender, ResolveEventArgs args)
+        internal static Assembly OnAssemblyResolve(object sender, ResolveEventArgs args)
         {
             var requestedName = new AssemblyName(args.Name).Name;
             if (string.IsNullOrWhiteSpace(requestedName))
@@ -304,6 +304,10 @@ namespace ShrinkModFramework
             if (!KnownAssemblyFiles.TryGetValue(requestedName, out var path) || !File.Exists(path))
                 return null;
 
+            if (ShrinkModLoader.AssemblyResolvePolicy != null &&
+                !ShrinkModLoader.AssemblyResolvePolicy(args.RequestingAssembly, new AssemblyName(args.Name), path))
+                return null;
+
             lock (ResolveLock)
             {
                 try