#3884: Upgrade GitHub Actions for Node 24 compatibility

## Summary Upgrade GitHub Actions to their latest versions to ensure compatibility with Node 24, as Node 20 will reach end-of-life in April 2026. ## Changes | Action | Old Version(s) | New Version | Release | Files | |--------|---------------|-------------|---------|-------| | `actions/checkout` | [`v4`](https://github.com/actions/checkout/releases/tag/v4) | [`v6`](https://github.com/actions/checkout/releases/tag/v6) | [Release](https://github.com/actions/checkout/releases/tag/v6) | ci.yml, docker-release.yml, install-smoke.yml, workflow-sanity.yml | | `actions/github-script` | [`v7`](https://github.com/actions/github-script/releases/tag/v7) | [`v8`](https://github.com/actions/github-script/releases/tag/v8) | [Release](https://github.com/actions/github-script/releases/tag/v8) | auto-response.yml | | `actions/labeler` | [`v5`](https://github.com/actions/labeler/releases/tag/v5) | [`v6`](https://github.com/actions/labeler/releases/tag/v6) | [Release](https://github.com/actions/labeler/releases/tag/v6) | labeler.yml | | `actions/setup-java` | [`v4`](https://github.com/actions/setup-java/releases/tag/v4) | [`v5`](https://github.com/actions/setup-java/releases/tag/v5) | [Release](https://github.com/actions/setup-java/releases/tag/v5) | ci.yml | | `actions/setup-node` | [`v4`](https://github.com/actions/setup-node/releases/tag/v4) | [`v6`](https://github.com/actions/setup-node/releases/tag/v6) | [Release](https://github.com/actions/setup-node/releases/tag/v6) | ci.yml | | `actions/setup-python` | [`v5`](https://github.com/actions/setup-python/releases/tag/v5) | [`v6`](https://github.com/actions/setup-python/releases/tag/v6) | [Release](https://github.com/actions/setup-python/releases/tag/v6) | ci.yml | ## Context Per [GitHub's announcement](https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/), Node 20 is being deprecated and runners will begin using Node 24 by default starting March 4th, 2026. ### Why this matters - **Node 20 EOL**: April 2026 - **Node 24 default**: March 4th, 2026 - **Action**: Update to latest action versions that support Node 24 ### Security Note Actions that were previously pinned to commit SHAs remain pinned to SHAs (updated to the latest release SHA) to maintain the security benefits of immutable references. ### Testing These changes only affect CI/CD workflow configurations and should not impact application functionality. The workflows should be tested by running them on a branch before merging. <!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> This PR updates GitHub Actions workflow dependencies to versions that run on newer Node runtimes (in response to GitHub Actions runner deprecating Node 20). Concretely, it bumps `actions/checkout` to `v6` across CI/release/sanity workflows, upgrades `actions/setup-node` to `v6`, `actions/setup-python` to `v6`, `actions/setup-java` to `v5`, and bumps `actions/github-script` / `actions/labeler` to their latest majors. These changes are isolated to `.github/workflows/*` and primarily affect how CI jobs check out code and provision toolchains on GitHub runners; application/runtime behavior is unchanged. <h3>Confidence Score: 5/5</h3> - This PR is safe to merge; it is a straightforward workflow action-version bump with no apparent behavioral regressions in the YAML. - All changes are limited to updating `uses:` versions for well-known GitHub Actions, and the workflow syntax/inputs remain consistent with current usage (no removed/renamed inputs observed in the edited steps). No secrets-handling or permission scope changes were introduced. - No files require special attention <!-- greptile_other_comments_section --> <!-- /greptile_comment -->