docs: improve `requested` from the `$app/server` module

[hyunbinseo]

(Update) The Client-requested refreshes docs seem to have most of the concerns resolved with the latest API. The requested docs could point here in the meantime. This isn't the first time I was referencing a less friendly, more API explanatory documentation, so such reference link could be really helpful.

---

Describe the problem

Current docs is not intuitive.

In the context of a remote command or form request ...

• What does 'context' mean here?
• Is that query same as $app/server.query? It does support the refresh method.

import { requested } from '$app/server';

for (const { arg, query } of requested(getPost, 5)) {
  // `arg` is the validated argument; `query` is bound to the client's
  // cache key. It's safe to throw away this promise -- SvelteKit will
  // await it and forward any errors to the client.
  void query.refresh();
}

The original PR #15562 had a more intuitive code block:

• requested should be called inside command or form callback.

// so this probably is a `*.remote.ts` file

import { query, command, requested } from '$app/server';

export const getPullRequests = query(GetPullRequestSchema, async () => {});

export const createPullRequest = command(CreatePullRequestSchema, async (args) => {
  /* do the stuff to create the pull request */

  // if your query uses async validators, you can also `for await` this.
  // it will run validation in parallel and yield results as they're available.
  for (const arg of requested(getPullRequests, 5)) {
    void getPullRequests(arg).refresh();
  }
});

Describe the proposed solution

Rough ideation. The #15562 PR body was much easier for me to understand than the current docs.

---

All query instance(s) refresh requested by the client can be accessed inside the command and form callbacks using the requested module.

import { command, requested } from '$app/server';

export const createPullRequest = command(CreatePullRequestSchema, async (data) => {
  /* do the stuff to create the pull request */

  for (const req of requested(
    getPost, // query function (vanilla batch, live)
    5, // limit
  )) {
    void req.query.refresh();
  }
});

Alternatives considered

No response

Importance

nice to have

Additional Information

No response