Floating surfaces

**Is your feature request related to a problem? Please describe.**
Some apps may want to expose a floating surface that is always sorted to the top

**Describe the solution you'd like**
A way to open a floating surface. This may require a system connection mark it as floating, so it would have to be requested through whatever the primary application (launcher) is.

**Describe alternatives you've considered**
System apps get input even if they are not in focus, and they are sorted on top. This is great for the primary application (launcher), but not so great for allowing third party applications for things like a floating window or a top bar etc.

**Additional context**
Focus switching for input passing will have to be sorted out for this.