Collect every blob hash currently referenced from a Y.Doc.
An entity's geometryRef.geomId points at a geometry top-level entry
whose blobHash (if any) we want to keep. Model slots can independently
own a portable STEP/IFCZIP sidecar. We also include any blobHash that
appears directly in geometry.params.<*> so apps that store auxiliary
blob refs in params (e.g. textures) survive gc.
Collect every blob hash currently referenced from a Y.Doc.
An entity's
geometryRef.geomIdpoints at ageometrytop-level entry whoseblobHash(if any) we want to keep. Model slots can independently own a portable STEP/IFCZIP sidecar. We also include anyblobHashthat appears directly ingeometry.params.<*>so apps that store auxiliary blob refs in params (e.g. textures) survive gc.