re-structure to monorepo.

packages/webapp/src/store/enhancers/monitorReducer.tsx

@@ -0,0 +1,18 @@
+// @ts-nocheck
+const round = number => Math.round(number * 100) / 100
+const monitorReducerEnhancer = createStore => (
+  reducer,
+  initialState,
+  enhancer
+) => {
+  const monitoredReducer = (state, action) => {
+    const start = performance.now()
+    const newState = reducer(state, action)
+    const end = performance.now()
+    const diff = round(end - start)
+    console.log('reducer process time:', diff)
+    return newState
+  }
+  return createStore(monitoredReducer, initialState, enhancer)
+}
+export default monitorReducerEnhancer