immer 的原理是什么，为什么它的性能更高

const state = {
  user: { id: 3 },
  role: { name: "admin" },
};
 
const proxyState = new Proxy(state, {
  get(target, prop) {
    return target[prop];
  },
});

//=> True
state !== proxyState;
 
//=> True
state.user === proxyState.user;