core: type: check if a class tries to implement an interface it doesn't extend or inherit

core/include/blue/core/status.h

@@ -39,6 +39,7 @@ typedef enum b_status_msg {
 	/* blue-object specific messages */
 	B_MSG_TYPE_REGISTRATION_FAILURE,
 	B_MSG_CLASS_INIT_FAILURE,
+	B_MSG_CLASS_SPECIFIES_UNKNOWN_INTERFACE,
 } b_status_msg;
 
 BLUE_API const char *b_status_to_string(b_status status);