✨ Unify Layering Strategies/Representation

[lsschmid]

What's the problem this feature will solve?

Currently, there exist different approaches to layers + different layering strategies:

1. Original QMAP layering here
2. Global NA layering from @ystade here
3. Dynamic layering from @lsschmid

It would be nice to (partially) unify these approaches.

Describe the solution you'd like

General Layer Class?