Add a way to handle GL context lost event.

[alan-wu]

Add event callback to handle GL Context Lost event, and method to remove and add maplibregl's map instance.

The changes also include turning the interleaved flag to true for Deck.gl's MapboxOverlay instance, this will avoid a new GL context being created.

[dbrnz]

Thanks, all looks good!

(I'll do a minor tidy to keep the //========== underlining the same length as the thing being underlined.)