wip, renderable bounding sphere

src/mol-geo/geometry/direct-volume/direct-volume.ts

src/mol-geo/geometry/lines/lines.ts

src/mol-geo/geometry/mesh/mesh.ts

src/mol-geo/geometry/points/points.ts

src/mol-gl/_spec/renderer.spec.ts

src/mol-gl/renderable.ts

src/mol-gl/renderable/direct-volume.ts

src/mol-gl/renderable/schema.ts

src/mol-gl/scene.ts

src/mol-math/geometry/primitives/sphere3d.ts

src/mol-math/linear-algebra/3d/vec4.ts