Unknown Entity General KV Property Support

[Cobertos]

Describe the solution you'd like For unknown entities (brush or point) current the only extended data you can get from it is the name of the entity as the object name prefix, it would be nice to have the option to import the entity type and associated properties to Blender's custom KV props that are stored under the object datablock.

As an alternative, just plain strings or even more influence on the import name would even be enough to hack with.

Additional context This is useful for example to convert something from Hammer -> Blender -> Game Engine where an importer on the engine side would be able to read the entities and act on the data. Unity's asset importer has a method to hook into for converting/doing stuff based on these properties.