task: #3615661 Pin the Events and News base recipes to released constraints

Plan issue: #3615661

Pins the last two cross-dependencies that were still tracking development branches. Both now have released versions, so the Educare 1.0.0-alpha1 release no longer depends on any x-dev constraint.

• drupal/varbase_events_base: 1.0.x-dev → ~1.0.0 (1.0.0-alpha1)
• drupal/varbase_news_base: 1.0.x-dev → ~1.0.0 (1.0.0-alpha1)

They were left at 1.0.x-dev in the version-bump merge request because neither recipe had a release at that point.

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