v0.13.0-beta.2

Fixed

• Deleting a floor in Home Assistant no longer leaves devices stuck as "placed". Devices on a deleted floor can be placed again, and a building whose floors were all deleted no longer appears on the Property tab or affects its scale. Nothing is erased: re-creating a floor with the same name brings its layout back. (#37)
• Floor tabs are reachable on phones. On narrow screens the floor tabs move to their own row under the header and scroll sideways when there are more floors than fit. Floor names stay visible instead of icons only. (#21)

Needs a Home Assistant restart (backend change).