[Maps] Display millions of points on a map

[kmartastic]

Customer wants to be able to visualize spatial patterns from millions of points by dimension or metric. This is based on the following ER: https://github.com/elastic/enhancements/issues/8397

For example:

Possible solutions:

• Distance-based grids for more specific, granular grids. This would enhance the choices of course, fine, finest, with a way to specify 10m x 10m or 250mi x 250mi.

• Generate vector tiles.
  [Maps] [Meta] Add .mvt vector tile support #58519
  [Maps] Add mvt format for ES-doc sources #74319

Solution to be discussed.

[elasticmachine]

Pinging @elastic/kibana-gis (Team:Geo)

[thomasneirynck]

Would require elastic/elasticsearch#58696

[thomasneirynck]

Closing with #114553