docs: Infer Context type

docs/content/1.get-started/2.usage.md

@@ -36,11 +36,12 @@ Initialize your tRPC backend using the `initTRPC` function and create your first
 
 ```ts [server/trpc/trpc.ts]
 import { initTRPC } from '@trpc/server'
+import { Context } from '@/server/trpc/context'
 
 // Avoid exporting the entire t-object since it's not very
 // descriptive and can be confusing to newcomers used to t
 // meaning translation in i18n libraries.
-const t = initTRPC.create()
+const t = initTRPC.context<Context>().create()
 
 // Base router and procedure helpers
 export const router = t.router
@@ -72,14 +73,27 @@ export type AppRouter = typeof appRouter
 ```ts [server/api/trpc/[trpc].ts]
 import { createNuxtApiHandler } from 'trpc-nuxt'
 import { appRouter } from '@/server/trpc/routers'
+import { createContext } from '@/server/trpc/context'
 
 // export API handler
 export default createNuxtApiHandler({
   router: appRouter,
-  createContext: () => ({}),
+  createContext,
 })
 ```
 
+```ts [server/trpc/context.ts]
+import { inferAsyncReturnType } from '@trpc/server'
+
+/**
+ * Creates context for an incoming request
+ * @link https://trpc.io/docs/context
+ */
+export const createContext = () => {}
+
+export type Context = inferAsyncReturnType<typeof createContext>;
+```
+
 ::
 
 ::alert{type=info}