fix(annotation/frontend_source): update offsets for new annotation only in updateAnnotation
fix(annotation/frontend_source): update offsets for new annotation only in updateAnnotation

janelia-flyem/neuroglancer,google/neuroglancer,google/neuroglancer,google/neuroglancer,janelia-flyem/neuroglancer,google/neuroglancer,google/neuroglancer,janelia-flyem/neuroglancer,google/neuroglancer,janelia-flyem/neuroglancer,google/neuroglancer,google/neuroglancer,janelia-flyem/neuroglancer