Save state in local storage

[kfarr]

As a user editing a splat I may close a tab without intending to which will result in loss of data such as selection area or previous edits.

Workaround: don't close a tab Alternative: a warning menu prior to closing a tab using system dialog box

Instead:

• save state in localstorage including current ply / splat being displayed, camera position, selected splats, scene origin, splat size #, it is ok if currently selected tool state is not retained.
• upon reloading application, check to see if state is saved and reload if exists

[simonbethke]

This https://github.com/playcanvas/supersplat/pull/279 is partially what you request. This is more for setting editor-setup related things. Once it is approved I would like to add an opened-file-history. Having the entire state preserved is not really practical as localStorage doesn't allow to store the amount of data that is required for a splat and this application is meant to run offline.