withParams doesn't allow to modify request on Cloudflare

[istarkov]

Describe the Issue

This typical Cloudflare code to modify a request (such as changing the url) fails when withParams is used
with the error Incorrect type for the 'fetcher' field on 'RequestInitializerDict': the provided value is not of type 'Fetcher'

import { Router, type IRequest, withParams } from 'itty-router';

const router = Router<IRequest, CFArgs>({
  before: [withParams],
});

router.get('*', (request) => {
  const req = new Request('https://example.com', request); // <-- fails with Incorrect type for the 'fetcher' field on 'RequestInitializerDict': the provided value is not of type 'Fetcher'.
  // ... change req headers etc  
});

export default { ...router };

The issue is this line https://github.com/kwhitley/itty-router/blob/v5.x/src/withParams.ts#L6
as seems like workerd is already wrapping request with rpc object and it has RPCBlabla type with bind method of the same type.

If bind is really needed better to check that obj[prop] instanceof Function ? obj[prop].bind ....

Fails in dev and production (when published to cloudflare)