feat: #3621736 Release Varbase 11.0.0

Release Varbase 11.0.0, the first stable release of the 11.0.x line, on Drupal ~11.4.0.

Plan issue: #3621736

What this changes

• composer.json: version 11.0.x-dev -> 11.0.0, and the six first-party dev pins moved to released constraints: drupal/varbase_starter, drupal/varbase_ai_base, drupal/varbase_api_base, drupal/varbase_auth_base, drupal/varbase_dev_base and drupal/varbase_i18n_base at ~1.0.0. No x-dev constraint remains in the profile.
• varbase.info.yml: version 11.0.x-dev -> 11.0.0.
• README.md: the Varbase version badge and its pipeline link move from 11.0.0-rc1 to 11.0.0.
• CHANGELOG.md: a new # 11.0.0 section, mirroring the release notes snippet in #3621736.

drupal/varbase_starter was already pinned at 11.0.0-rc1 and was moved back to a dev branch by #3621480, so that one repin restores the rc1 state rather than pinning for the first time.

Stability, stated plainly

Varbase 11.0.0 is a stable release, but it does not resolve on a project using Composer's default minimum-stability: stable. Four requirements have no stable release for the major the profile needs: drupal/entity_clone: ~2 (newest 2.2.0-beta1, no stable release at all), drupal/rabbit_hole: ~2 (newest 2.0.0-beta2; its stables are on the older 8.x-1.x line), drupal/ultimate_cron: ~2 (newest 8.x-2.0-beta1; stables are Drupal 7 only) and drupal/advanced_text_formatter: ~3 (newest 3.0.0-rc2, newest stable 2.1.1).

That is by design and is deliberately not worked around here. The profile is consumed through Varbase Project, whose root sets minimum-stability: dev with prefer-stable: true. Those four packages live in the profile precisely so that removing them from the site templates and base recipes could not take them away from existing sites, which is what made the templates installable on Drupal CMS. Upstream stable releases are requested in #2660208, #3621376, #3621362 and #3189738.

Not in this MR

The tag, the release node, the change-issue close cycle and Back to DEV are separate steps, taken after this is reviewed and merged.

AI-Generated: Yes

Checkpoints:

• File an issue
• Addition/Change/Update/Fix
• Testing to ensure no regression
• Automated unit testing coverage
• Automated functional testing coverage
• UX/UI designer responsibilities
• Readability
• Accessibility
• Performance
• Security
• Developer Documentation
• User Guide Documentation
• Reviewed by human
• Code review by maintainers
• Full testing and approval
• Credit contributors
• Review with the product owner
• Release notes snippet
• Release