refactor(async_rollout_worker): renamed tool variables to mirror grpo_trainer.py

[casinca]

What does this PR do?

This is a small refactor following @qgallouedec #5330 (comment) in my previous PR.

To harmonize async_rollout_worker.py with grpo_trainer.py tool variables:

_build_messages_suffix_ids → _get_tool_suffix_ids
messages → tool_messages
template_messages → dummy_messages
prefix_and_messages_ids → full_ids
tool_suffix_ids → suffix_ids

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• Did you read the contributor guideline,
  Pull Request section?
• Was this discussed/approved via a GitHub issue? Please add a link
  to it if that's the case.
• Did you make sure to update the documentation with your changes?
• Did you write any new necessary tests?

Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

---

Note

Low Risk
Pure refactor limited to tool-message suffix tokenization and variable renames; behavior should be unchanged but could affect tool-call prompting if the suffix slicing logic is accidentally altered.

Overview
Refactors AsyncRolloutWorker tool-call handling to mirror grpo_trainer.py naming and structure.

Renames _build_messages_suffix_ids to _get_tool_suffix_ids and consistently renames related locals (messages→tool_messages, template_messages→dummy_messages, prefix_and_messages_ids→full_ids, tool_suffix_ids→suffix_ids) while keeping the same suffix-ID computation and call site in _generate_one.

^{Written by Cursor Bugbot for commit 0da28b1. This will update automatically on new commits. Configure here.}

[qgallouedec]

Thanks!

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.