github-actions: bump actions/cache from 4 to 6

[dependabot]

Bumps actions/cache from 4 to 6.

Release notes

Sourced from actions/cache's releases.

v6.0.0

What's Changed

• Update packages, migrate to ESM by @​Samirat in actions/cache#1760

Full Changelog: actions/cache@v5...v6.0.0

v5.1.0

What's Changed

• Bump @​actions/cache to v5.1.0 - handle read-only cache access by @​jasongin in actions/cache#1775

Full Changelog: actions/cache@v5...v5.1.0

v5.0.5

What's Changed

• Update ts-http-runtime dependency by @​yacaovsnc in actions/cache#1747

Full Changelog: actions/cache@v5...v5.0.5

v5.0.4

What's Changed

• Add release instructions and update maintainer docs by @​Link- in actions/cache#1696
• Potential fix for code scanning alert no. 52: Workflow does not contain permissions by @​Link- in actions/cache#1697
• Fix workflow permissions and cleanup workflow names / formatting by @​Link- in actions/cache#1699
• docs: Update examples to use the latest version by @​XZTDean in actions/cache#1690
• Fix proxy integration tests by @​Link- in actions/cache#1701
• Fix cache key in examples.md for bun.lock by @​RyPeck in actions/cache#1722
• Update dependencies & patch security vulnerabilities by @​Link- in actions/cache#1738

New Contributors

• @​XZTDean made their first contribution in actions/cache#1690
• @​RyPeck made their first contribution in actions/cache#1722

Full Changelog: actions/cache@v5...v5.0.4

v5.0.3

What's Changed

• Bump @actions/cache to v5.0.5 (Resolves: https://github.com/actions/cache/security/dependabot/33)
• Bump @actions/core to v2.0.3

Full Changelog: actions/cache@v5...v5.0.3

v.5.0.2

v5.0.2

What's Changed

... (truncated)

Changelog

Sourced from actions/cache's changelog.

Releases

How to prepare a release

[!NOTE] Relevant for maintainers with write access only.

1. Switch to a new branch from main.
2. Run npm test to ensure all tests are passing.
3. Update the version in https://github.com/actions/cache/blob/main/package.json.
4. Run npm run build to update the compiled files.
5. Update this https://github.com/actions/cache/blob/main/RELEASES.md with the new version and changes in the ## Changelog section.
6. Run licensed cache to update the license report.
7. Run licensed status and resolve any warnings by updating the https://github.com/actions/cache/blob/main/.licensed.yml file with the exceptions.
8. Commit your changes and push your branch upstream.
9. Open a pull request against main and get it reviewed and merged.
10. Draft a new release https://github.com/actions/cache/releases use the same version number used in package.json
    1. Create a new tag with the version number.
    2. Auto generate release notes and update them to match the changes you made in RELEASES.md.
    3. Toggle the set as the latest release option.
    4. Publish the release.
11. Navigate to https://github.com/actions/cache/actions/workflows/release-new-action-version.yml
    1. There should be a workflow run queued with the same version number.
    2. Approve the run to publish the new version and update the major tags for this action.

Changelog

6.1.0

• Bump @actions/cache to v6.1.0 to pick up actions/toolkit#2435 Handle cache write error due to read-only token
• Switch redundant "Cache save failed" warning to debug log in save-only

6.0.0

• Updated @actions/cache to ^6.0.1, @actions/core to ^3.0.1, @actions/exec to ^3.0.0, @actions/io to ^3.0.2
• Migrated to ESM module system
• Upgraded Jest to v30 and test infrastructure to be ESM compatible

5.0.4

• Bump minimatch to v3.1.5 (fixes ReDoS via globstar patterns)
• Bump undici to v6.24.1 (WebSocket decompression bomb protection, header validation fixes)
• Bump fast-xml-parser to v5.5.6

5.0.3

• Bump @actions/cache to v5.0.5 (Resolves: https://github.com/actions/cache/security/dependabot/33)
• Bump @actions/core to v2.0.3

5.0.2

... (truncated)

Commits

• 55cc834 Merge pull request #1768 from jasongin/readonly-cache
• d8cd72f Bump @​actions/cache to v6.1.0 - handle cache write error due to RO token
• 2c8a9bd Merge pull request #1760 from actions/samirat/esm_migration_and_package_update
• e9b91fd Prettier fixes
• e4884b8 Rebuild dist
• 10baf01 Fixed licenses
• e39b386 Fix test mock return order
• b692820 PR feedback
• 6074912 Rebuild dist bundles as ESM to match type:module
• 5a912e8 Fix lint and jest issues
• Additional commits viewable in compare view

[bgentry]

@dependabot rebase

[bgentry]

🤖 Codex review: Approved after dependency security and compatibility review.

Upgrade

• actions/cache: v4 → v6
• Reviewed head: 00aa9f9184b6db27362e927cd1638a108e5d0022
• Reviewed action target: v6 → 55cc8345863c7cc4c66a329aec7e433d2d1c52a9

Security review

• The reviewed v4 and v6 tags resolve to verified upstream commits, and the committed action bundles and dependency graph were inspected. v6 moves the runtime to Node 24/ESM, shrinks the production graph, and removes the old graph's reported high/moderate vulnerable paths.
• Workflow scope is unchanged: only .eslintcache is restored/saved under the existing branch/key isolation, with no added token permission or input expansion.
• v6 still bundles undici@6.27.0, which has three medium advisories fixed in 6.28.0. Static reachability review found the affected blob, cookie, and retry APIs unused by this action and workflow.
• The Dependabot rebase changed only the base tree; the action version, tag target, workflow inputs, permissions, and execution context are unchanged, so the artifact evidence is reusable.

Compatibility verification

• Current-head GitHub JS Lint passed, exercising actions/cache@v6 on the hosted runner; JS Build/Test, release, Go, and riverui image checks also passed.
• npm ci --ignore-scripts — passed.
• npm run lint — passed.
• npm run test:once — passed (34 files, 233 tests).
• npm run build — passed.
• The riverproui image failure is at AWS role assumption in an unrelated workflow path.

Residual risk

• @v6 is a mutable major tag, and dormant vulnerable Undici code remains bundled pending an upstream refresh. No reachable or blocking issue identified for this use.