* Add zustand to app
* Begin replacing ObsEditProvider with zustand for global state
* Use store and add tests
* Fix bugs
* Add test to check for deleted photos in StandardCamera
* Make sure evidence is only added to current observation; submit comment with ID on ObsDetail
* Fix ObsEditWithoutProvider tests
* Move store to where it's needed
* Fix tests
* Await evidence being added to obsPhotos from camera
* Add a note about slices to useStore