build expressions using multiple searches

[hrodmn]

It would be really cool to be able to generate visualizations that use assets from multiple pgstac searches. For example:

• showing differences in NDVI or land cover classification from a single collection at different points in time
• generating expressions that combine assets from multiple collections (e.g. DEM + land cover)

It would be very powerful because the different data sources might have different extents/resolutions but the arrays created by the mosaic readers for methods like tile would be compatible.

[vincentsarago]

sounds like layer composition!

Sadly, I don't see a straight forward path to do this 😓