test(e2e): add developer user flow validation helper

[joaoopereira]

What was done

Add an opt-in developer helper for validating CLI changes through a fresh MES project: portal login, initialization, devcontainer startup and credential synchronization, six package scaffolds, local stack installation, LBO generation, package builds, headless login through port 80, and package packing.

Each MES version uses its own config and license. Commands and results are recorded with credentials redacted; failed runs retain their project and can resume. Browser setup installs Chromium's Linux dependencies, and the homepage check requires visible Administration and Business Data entries inside .menu-sub-menu.

Playwright and the devcontainer CLI are isolated dependencies of this helper. No changelog entry or version bump is needed for this test tooling.

Validation checklist

• Helper unit tests: 8 passed.
• Browser smoke test passed, covering orchestration, password confirmation, resume, failure handling, and cleanup.
• Sidebar selector and login navigation verified against the supplied MES 10 reference environment.
• Real v10 scaffolding, installation, LBO generation, and six package builds passed; six packages packed in separate diagnostics.
• Complete real end-to-end run: the earlier v10 local stack failed its security setup integration entry because the host could not resolve securityportal:8080. The v11 run is still in progress.
• Main WorkItem is linked (none supplied).
• Target branch is development.

The running v11 environment was left untouched during branch and PR creation.

[github-actions]

.NET Test Results

View full test report

[github-actions]

Package	Line Rate	Branch Rate	Health
cmf	48%	48%	➖
core	76%	59%	✔
Summary	59% (6418 / 10809)	54% (3346 / 6248)	➖