NWhat are the use cases? You should know that tRPC only really cares about passing JSON back and forth. If you want to shuttle Binary then you're out of luck, though there is talk of supporting additional content types like form-data in the future
NThe idiomatic way to upload or download binary is to use a storage service which can generate secure URLs for the backend and send to the frontend
NYes so RPC is a little different to REST, in general you should imagine it being like calling functions within your application. You can only pass arguments and receive returns
NYou could probably wrap up the trpc hooks into some custom hooks which handle these cross-cutting inputs and just expose the stuff you want components to care about
NFor return data, rather than response headers it would be best to just wrap up your return data into a return which includes what used to be in response headers
NYes, the problem will be getting those response headers to your client code as only the body gets passed back generally
Nmiddlewares are definitely powerful enough