Compat REST client drops security from the v0.3 extended agent card #1418

What happens

CompatRestTransport.get_extended_agent_card against a v0.3 server turns an HTTP bearer scheme into an empty OpenIdConnect scheme, and card and skill security come back as [{}].

Why

It parses GET /v1/card as v0.3 proto JSON. v0.3 servers, including REST03Handler, send the pydantic card JSON. CompatJsonRpcTransport already parses it with types_v03.AgentCard.model_validate.

Version

main @ 11f1116