feat: Adds two examples to demo 3d maps.

[willum070]

This PR adds two examples to demonstrate the use of 3D maps.

• map-3d-simple shows the simplest possible 3d map.
• map-3d-events shows how to handle events and has a nifty UI which still needs some work (it's positioned wrong).

🦕

[snippet-bot]

Here is the summary of changes.

You are about to add 4 region tags.

• samples/map-3d-events/index.ts:7, tag maps_map_3d_event
• samples/map-3d-events/style.scss:9, tag maps_map_3d_events
• samples/map-3d-simple/index.ts:7, tag maps_3d_map_simple
• samples/map-3d-simple/style.scss:9, tag maps_3d_map_simple

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