mol-plugin-ui: fixed crash caused by invalid state during updates

src/mol-plugin-state/manager/structure/hierarchy-state.ts

src/mol-plugin-ui/state/tree.tsx

src/mol-plugin-ui/structure/components.tsx

src/mol-plugin-ui/structure/generic.tsx

src/mol-plugin-ui/structure/measurements.tsx

src/mol-plugin-ui/structure/source.tsx

src/mol-plugin-ui/structure/volume.tsx

...havior/dynamic/custom-props/rcsb/ui/assembly-symmetry.tsx

src/mol-plugin/context.ts

src/mol-state/object.ts

src/mol-state/state.ts