Set rendererer ready properly

[oterral]

Some map events (like 'rendercomplete') are never triggered because the renderer is never set as ready.

It's a variant of #258.

Instead of using the load event we use the idle which is a more reliable event because it is triggered on each moveend/zoomend or when you programmatically change the maplibre style layers .

This PR also contains fixes :

• fix: we must compare the visual size of the map not canvas attributes #288
• fix: use the new tileManagers property for newer maplibre-gl version #274