Improve west build: split off setup of build directory

[brondani]

Fixes

• Address first item from Improve Zephyr Build ARM-software/vscode-cmsis-csolution#448 (comment)

Changes

• Detach setup of build directory (and generation of compilation database), setting it as a west build dependency

Screenshot

First build after tmp/out cleaning:

Successive builds:

Checklist

• 🤖 This change is covered by unit tests (if applicable).
• 🤹 Manual testing has been performed (if necessary).
• 🛡️ Security impacts have been considered (if relevant).
• 📖 Documentation updates are complete (if required).
• 🧠 Third-party dependencies and TPIP updated (if required).

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[qltysh]

Coverage Impact

⬆️ Merging this pull request will increase total coverage on main by 0.06%.

Modified Files with Diff Coverage (1)

Rating	File	% Diff	Uncovered Line #s
	pkg/maker/west.go	100.0%
	Total	100.0%

🚦 See full report on Qlty Cloud »

🛟 Help

• Diff Coverage: Coverage for added or modified lines of code (excludes deleted files). Learn more.

• Total Coverage: Coverage for the whole repository, calculated as the sum of all File Coverage. Learn more.

• File Coverage: Covered Lines divided by Covered Lines plus Missed Lines. (Excludes non-executable lines including blank lines and comments.)

  • Indirect Changes: Changes to File Coverage for files that were not modified in this PR. Learn more.

[github-actions]

Test Results

  6 files  ±0   30 suites  ±0   1s ⏱️ ±0s
 98 tests ±0   98 ✅ ±0  0 💤 ±0  0 ❌ ±0 
588 runs  ±0  588 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit f933f28. ± Comparison against base commit c9a2cbf.