v11 types ProcedureBuilder & MiddlewareBuilder - tRPC

You used to be able to import these types directly from `@trpc/server`. With v11 you can only import them via `unstable-core-do-not-import`. I have some properties on a class that should hold a `t.middleware` and a `t.procedure`. What's the recommended way to type my `Middleware` and `Procedure` in v11? ```ts type Middleware = ? type Procedure = ? const t = initTRPC.create() class MyClass { private middleware: Middleware = t.middleware(({ next }) => next()) private proc: Procedure = t.procedure public procedure(procedure: Procedure) { this.proc = procedure return this } public use(middleware: Middleware) { this.middleware = middleware return this } ```