QVAC-19547 test[skiplog]: add strict Snap SDK e2e coverage

[Victor-Rodzko]

🎯 What problem does this PR solve?

• SDK regressions caused by strict Snap confinement, packaged native libraries, or revision-scoped storage are not observable in the existing desktop and Electron runs.
• In particular, SDK state must remain under SNAP_USER_COMMON when a Snap revision changes instead of following the revision-specific home directory.

📝 How does it solve it?

• Packages the existing Electron consumer as a strict core22 Snap through an isolated LXD Snapcraft build, preserving the standard Electron model and addon coverage.
• Adds Snap-specific storage assertions and a two-revision refresh probe that verifies worker and registry data remain available from common storage.
• Adds a manual-only snap target to test-sdk.yml; PR label workflows remain unchanged.
• Uses the temporary package published from qvac-test-suite#84, which provides the Snap build/install/bootstrap/consumer commands.

🧪 How was it tested?

• Installed and resolved @tetherto/qvac-test-suite@0.9.0-tmp.pr-84.runid-29430579062 from the registry.
• Built the SDK e2e TypeScript consumer with the published framework package.
• Ran SDK lint with zero warnings.
• Ran snap-worker-storage.test.ts: 1/1 test and 4/4 assertions passed across simulated revision homes.
• Validated both modified workflows with actionlint and checked all changed e2e files with Prettier.
• The strict Snap package/refresh flow requires the manual Linux LXD runner and was not executed on the local macOS host.

[github-actions]

Review Status

Current Status: ❌ PENDING
Approvals so far: none

Pending reviews: Needs 1 Management or Team Lead, and 1 more from Management, Team Lead, or Member.