public Map<String, Schema> getSynthesizedSchemas() {
        return Collections.unmodifiableMap(synthesizedSchemas);
    }
Gets all of the synthesized schemas that needed to be created while
generating the OpenAPI artifact.

@return Returns the "synthesized" schemas as an immutable map.
smithy-openapi/src/main/java/software/amazon/smithy/openapi/fromsmithy/Context.java