[FireAtlas] Possibility to update grid size once you are in the atlas

[spydon]

What could be improved

Add the possibility to update grid size once you are in the atlas

Why should this be improved

So that you don't have to recreate the atlas to set a new grid size

Risks

Might be complicated if there already are selections in the atlas

More information

No response

Other

• [ ] Are you interested in working on a PR for this?