Tweaked packing settings to keep system files in Data/Managed

IPA.Injector/PostBuild.msbuild

@@ -12,6 +12,9 @@
     <ItemGroup>
       <SystemFiles Include="$(OPath)IPA.Injector.*" />
       <SystemFiles Include="$(OPath)IPA.Loader.*" />
+      <SystemFiles Include="$(OPath)AsyncBridge.*" />
+      <SystemFiles Include="$(OPath)System.Threading.*" />
+      <SystemFiles Include="$(OPath)Net3-Proxy.*" />
       <SystemFiles Include="$(OPath)Libraries\Mono\**\*" />
       <OldLibFiles Include="$(OPath)Libs\**\*" />
     </ItemGroup>

docs/docfx.json

@@ -11,7 +11,8 @@
         "**/IPA.Tests.csproj",
         "TMP Exporter/**.csproj",
         "BuildTools/**.csproj",
-        "Doorstop/**.csproj"
+        "Doorstop/**.csproj",
+        "Net3-Proxy/**.csproj"
       ]
     }],
     "dest": "api",