Fix bugs in CI workflows, utils logic, and documentation syntax errors
Author: Goutam16-Withcode
Pull request: yes

# What does this PR do?

This PR addresses a variety of bugs and syntax errors discovered across CI workflows, utility scripts, and model documentation.

**1. CI Workflow Fixes:**
* **CircleCI:** Added the missing `Circle-Token` authorization header to the `curl` command in `.circleci/config.yml` when retrieving artifact paths from the v2 API to prevent rate-limiting or fetching failures.
* **GitHub Actions:** Fixed unquoted shell variables in `.github/workflows/self-comment-ci.yml` that were causing `[: !=: unary operator expected` bash syntax errors. Also fixed the string interpolation for `body` strings in the `gh api` calls to prevent structural spacing issues.

**2. Utility Script Fixes:**
* **Doc TOC Checker:** Added a safety check (`if "sections" in section`) in `utils/check_doc_toc.py` to prevent a `KeyError` from being thrown when iterating through sections that do not have nested child nodes.

**3. Documentation Syntax Fixes:**
* **LLaVA-OneVision:** Fixed a missing comma in `llava_onevision.md` causing a Python `SyntaxError` in the usage example.
* **LLaVA-NeXT-Video:** Removed an accidental double-comma passed to `.from_pretrained()` in `llava_next_video.md`.
* **Mistral 3 & LongCatFlash:** Fixed missing commas and indentation errors in the initialization code examples inside `mistral3.md` and `longcat_flash.md`.
* **MaskFormer:** Updated the broken issue template link (changed `bug-report.md` to `bug-report.yml`) in `maskformer.md`.

## Code Agent Policy

The Transformers repo is currently being overwhelmed by a large number of PRs and issue comments written by
code agents. We are currently bottlenecked by our ability to review and respond to them. As a result, 
**we ask that new users do not submit pure code agent PRs** at this time. 
You may use code agents in drafting or to help you diagnose issues. We'd also ask autonomous "OpenClaw"-like agents
not to open any PRs or issues for the moment.

PRs that appear to be fully agent-written will probably be closed without review, and we may block users who do this
repeatedly or maliciously. 

This is a rapidly-evolving situation that's causing significant shockwaves in the open-source community. As a result, 
this policy is likely to be updated regularly in the near future. For more information, please read `CONTRIBUTING.md`.

- [x] I confirm that this is not a pure code agent PR.

## Before submitting
- [x] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
- [x] Did you read the contributor guideline,
      Pull Request section?
- [ ] Was this discussed/approved via a Github issue or the forum? Please add a link
      to it if that's the case.
- [x] Did you make sure to update the documentation with your changes? Here are the
      documentation guidelines, and
      here are tips on formatting docstrings.
- [ ] 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.

@ydshieh @stevhliu


Comments:
cc @ydshieh @tarekziade since the most significant changes are the circleCI config