Enable/disable streaming on a per object basis.

Streaming causes several issues like certain objects parented to them ending up in the wrong location or logic nodes "Spawn object" resulting in the game freezing.

Therefore it would be nice with a little tickbox in Blenders object properties panel to let the user decide which objects to stream and which not to stream.

No files, tests, or entry points are named. Start by tracing the existing streaming behavior and the Blender object-properties integration, then determine how the choice is passed per object. Done means users can toggle streaming independently for each object without the reported parenting errors or Spawn object freezes.

Written by the indexing model from the issue text.