Sloth's subfloor vismask adventure (#35347)

* Add a subfloor vismask

Significantly cuts down on sent entity count.

* More optimisations

* Fix command

* Fixes

* namespace cleanup

* Review

* Vismasks

* Content update

* Bandaid

* awewa

* Revert these

* reh

* Update Content.Shared/SubFloor/TrayScannerComponent.cs

---------

Co-authored-by: slarticodefast <161409025+slarticodefast@users.noreply.github.com>

Content.IntegrationTests/Tests/PrototypeSaveTest.cs

@@ -35,7 +35,6 @@ public sealed class PrototypeSaveTest
         await using var pair = await PoolManager.GetServerClient();
         var server = pair.Server;
 
-        var mapManager = server.ResolveDependency<IMapManager>();
         var entityMan = server.ResolveDependency<IEntityManager>();
         var prototypeMan = server.ResolveDependency<IPrototypeManager>();
         var seriMan = server.ResolveDependency<ISerializationManager>();