proxies created before a YDoc update, do not update

[tobowers]

I came across this in our syncing, but minimized it down to the below example. The behavior I'm seeing is that if you save a proxy to a variable, that proxy will not update when the document updates.

  it.only('updates a saved proxy', async () => {
    const doc = new Y.Doc()
    const shape = {
      data: {} as Record<string, any>
    }

    const store = syncedStore(shape, doc)

    store.data.someObj = {}
    store.data.someObj.hello = 'world'

    const originalObj = store.data.someObj

    const mp = new Y.Map()
    mp.set('hello', 'world')
    doc.getMap('data').set('someObj',  mp)

    // this passes
    expect(store.data.someObj).toEqual({ hello: 'world' })
    // this fails
    expect(originalObj.hello).toEqual('world')
  })
``