Use of `/trpc` as URL to `createTRPCHandle` should be documented as a caveat

[angrytongan]

Describe the bug
Access a sveltekit route starting with /trpc results in an error. Example: with a SvelteKit route of src/routes/trpc+zod:

{"error":{"message":"No \"query\"-procedure on path \"zod\"","code":-32004,"data":{"code":"NOT_FOUND","httpStatus":404,
...

Cause
createTRPCHandle uses /trpc as the default pathname for the handler. Not a bug, but a note in Recipes and caveats would be awesome.

Thanks for a great library!