perf(index): remove redundant optional chaining

[Fdawgs]

routeOptions.config is always defined, so the optional chaining is redundant. Redundant optional chaining has a small performance impact: https://adventures.nodeland.dev/archive/noop-functions-vs-optional-chaining-a-performance/

For example, a basic route of:

fastify.get('/', async () => {
    return { message: 'ok' }
  })

would have the following routeOptions property:

{
  method: "GET",
  url: "/",
  bodyLimit: 1048576,
  attachValidation: false,
  logLevel: "",
  exposeHeadRoute: true,
  prefixTrailingSlash: "both",
  handler: function () { [native code] },
  config: {
    url: "/",
    method: "GET",
  },
  schema: undefined,
  version: undefined,
}

Checklist

• run npm run test && npm run benchmark --if-present
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[Copilot]

Pull request overview

This PR fixes a potential TypeError by adding a safe fallback when destructuring request.routeOptions?.config. The optional chaining operator ?. can short-circuit to undefined when either request.routeOptions or config is undefined, and destructuring from undefined throws a TypeError.

Key Changes:

• Added ?? {} fallback for optional chaining destructuring in two onRequest hooks

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

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