setup3DTiles
Set up a 3D Tiles GeoPackage extension blob table for tableName. Idempotent: re-opening an existing 3D Tiles content registers the same row + extension entry.
Schema follows the OGC 3D Tiles GeoPackage Extension proposal — the per-dataset blob table is created by the caller's DAO (GpkgBlobRow columns), and this method stitches it into the GPKG content + extension registries so external readers see it as a documented extension rather than an anonymous user table.