The Outgoing trait now has no attributes except incoming_no_deserialize, it looks for any references and lifetimes in a struct declaration and removes them. The point of the Outgoing trait is to allow references to be serialized and owned values to come out of deserialization. It has no ability to wrap values in Raw (then EventResult).
ruma-api
ruma-api contains core types used to define the requests and responses for each endpoint in the various Matrix API specifications. These types can be shared by client and server code for all Matrix APIs.
Documentation
ruma-api has comprehensive documentation available on docs.rs.