ci: upgrade workflow actions to Node24-compatible majors

[ShixiangWang]

Summary

Two CI fixes bundled in one PR (both validated by the same CI runs):

1. Bump all GitHub Actions to their latest Node24-based majors to
   resolve the "Node.js 20 is deprecated" runner annotations (issue 工程优化专项：站点存储瘦身 × CI 构建提速 × 工作流可扩展性（含实测数据与分阶段方案） #306,
   Phase 0 item C5).
2. Require the github-pages environment for the deploy-pages job —
   the first deploy-pages run on main (merge of ci: migrate Pages deploy to actions/deploy-pages #308) failed with
   HttpError: Missing environment because actions/deploy-pages requires
   the job to declare environment: name: github-pages. The legacy
   quarto publish gh-pages target never needed one.

1. Action upgrades (version-only)

Action	From	To
actions/checkout	v4	v7
actions/setup-python	v5	v7
actions/github-script	v7	v9
actions/upload-pages-artifact	v3	v5 (wraps upload-artifact v7)
actions/upload-artifact	v4	v7
actions/cache (incl. restore/save)	v4	v6
julia-actions/setup-julia	v2	v3
tj-actions/changed-files	v46.0.5	v47.0.6

Already latest (kept): actions/configure-pages@v6, actions/deploy-pages@v5,
quarto-dev/quarto-actions@v2, r-lib/actions@v2. All upgraded majors
verified to declare using: node24.

2. Environment fix (additive, 10 lines)

Both publish workflow jobs get:

environment:
  name: github-pages

The github-pages environment already exists in the repo with a branch
policy allowing main (and legacy gh-pages). This is the documented
requirement of actions/deploy-pages.

Verification

• All 8 workflow YAML files parse (yaml.safe_load).
• PR CI runs both publish workflows end-to-end; the merge push will be
  the first fully-correct deploy-pages deploy.

Refs: #306, follow-up to #308

🤖 Generated with Claude Code

[github-actions]

✅ QMD Format Check

No new QMD tutorial files to check.

Automated check by the PR Review workflow.
See contribution guidance for the expected tutorial format.

[ShixiangWang]

⚠️ Heads-up before merging this PR: the first deploy-pages run on main (run 37889595653 for merge of #308) failed at Deploy to GitHub Pages with:

HttpError: Missing environment. Ensure your workflow's deployment job has an environment.

Root cause: actions/deploy-pages requires the job to declare environment: name: github-pages (the Pages deployment API rejects requests without it). The legacy quarto publish gh-pages target didn't need this, so the workflows never had it.

Fix in progress: adding the environment block to both publish workflow jobs (follow-up commit to this PR so it's covered by the same CI validation).

[github-actions]

✅ QMD Format Check

No new QMD tutorial files to check.

Automated check by the PR Review workflow.
See contribution guidance for the expected tutorial format.

[github-actions]

✅ QMD Format Check

No new QMD tutorial files to check.

Automated check by the PR Review workflow.
See contribution guidance for the expected tutorial format.

[ShixiangWang]

🔧 修复 PR CI 失败：部署拆分为独立 job

根因确认(来自 annotations):Branch "refs/pull/309/merge" is not allowed to deploy to github-pages due to environment protection rules.

仓库的 github-pages environment 配置了 deployment branch policy,只允许 main 和 gh-pages 部署。pull_request 事件的 ref 是 refs/pull/<n>/merge,在被 protection rules 拦截,job 直接失败(无任何 step 日志)。

修复(c549e0b):将 Configure/Deploy Pages 步骤从 build-deploy 拆分到独立的 deploy job:

• needs: build-deploy,使用其上传的 github-pages artifact
• if: github.event_name != 'pull_request' — PR 上只构建+上传 artifact,永不对 environment 发起部署
• push/schedule/dispatch 时正常部署

这也意味着 PR 不再依赖 environment 检查,CI 可以完全转绿。

🤖 Generated with Claude Code