Query extension support does not allow Query extension JSON syntax

[philvarner]

The docs say The query filter will also accept complete JSON as per the specification., but it only accepts the simplified syntax that pystac-client made up (e.g., eo:cloud_cover<10). Not sure if we want to fix this or change the documentation.

[matthewhanson]

This should be fixed to accept JSON, which I thought it was doing here:

pystac-client/pystac_client/item_search.py

Line 297 in 506cd4c

else:

If the query is not a list then it's a Dict (QueryLike type), which is then passed through as is.

[philvarner]

problem with that code is that the if is

if isinstance(value, list):

and it's a List[Dict[str,Any]] rather than a Dict[str,Any] because the arg has nargs="*",