ci: fix sdk cache check

[UdjinM6]

Issue being fixed or feature implemented

It's possible to end up in a situation where depends-<hash>-mac cache still exists but depends-sdks one was purged by github already. (example https://github.com/UdjinM6/dash/actions/runs/21221002352)

What was done?

Make sure SDKs cache exists regardless of depends-<hash>-mac presence.

How Has This Been Tested?

patched develop, w/o sdks cache: https://github.com/UdjinM6/dash/actions/runs/21293050632/job/61291689128
patched develop, w/ sdks cache: https://github.com/UdjinM6/dash/actions/runs/21293174715/job/61292153721
this branch, no sdks cache on develop: https://github.com/UdjinM6/dash/actions/runs/21292572578/job/61290004717

Breaking Changes

n/a

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional/e2e tests
• I have made corresponding changes to the documentation
• I have assigned this pull request to a milestone (for repository code-owners and collaborators only)

[github-actions]

✅ No Merge Conflicts Detected

This PR currently has no conflicts with other open PRs.

[coderabbitai]

Walkthrough

This pull request modifies the GitHub Actions workflow to implement SDK caching for macOS builds. The changes introduce a two-step caching strategy: a "check-cache" job that generates and caches SDKs (or restores from cache), and updates the main build job to restore pre-cached SDKs instead of generating them at build time. The setup-sdk script is added to the initial checkout, and the build process now depends on restored cache artifacts with a fail-on-cache-miss constraint. The cache key is derived from a hash of darwin.mk to invalidate when dependencies change.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'ci: fix sdk cache check' clearly and concisely describes the main change: fixing an SDK cache-related issue in the CI workflow configuration.
Description check	✅ Passed	The description is directly related to the changeset, explaining the issue with SDK cache being purged independently and how the changes address this by decoupling SDK cache management from the depends cache.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}