message: refactoring and static typing for MainContainer
diff: import React, {useState, useEffect} from 'react';
  import SnapshotsContainer from '../SnapshotContainer';
  import VisualContainer from '../VisualContainer';
  -import {stateSnapshot} from '../../../types/';
  +import {stateSnapshot, selectedTypes} from '../../../types/';
  interface MainContainerProps {
  // snapshotHistory is an array of stateSnapshots
  snapshotHistory: stateSnapshot[];
  - selected: any;
  - setSelected: any;
  - filter: any;
  + selected: selectedTypes[];
  + setSelected: React.Dispatch<React.SetStateAction<selectedTypes[]>>;
  + filter: stateSnapshot[];
  }
  // wraps entire application
  @@ -19,7 +19,9 @@ const MainContainer: React.FC<MainContainerProps> = ({
  filter,
  }) => {
  // useState hook to update the index of current snapshot rendered in devtool
  - const [renderIndex, setRenderIndex] = useState(snapshotHistory.length - 1);
  + const [renderIndex, setRenderIndex] = useState<number>(
  + snapshotHistory.length - 1,
  + );
  // Todo: usestate hook to update an array with all of the delta snapshots
  