Add inteligent bound constraint

[dannyleech]

Constraining the bounds to England or the UK doesnt always produce the best results when near the borders. For example you can centre the map on a location if it is onthe edge of the bounds constraint with maplibre the viewport is constrained. With ESRI the centre is constrained which helps here but is even worse when at low zoom levels as it effectively stops working. We need a zoom based constrain, this could be built into the core.