chore: #3620507 Back to DEV

Closes #3620507.

Returns the branch to development after the 1.0.0-beta1 release.

• composer.json: version 1.0.0-beta1 -> 1.0.x-dev, and the five sibling recipe dependencies back to their dev branches (varbase_components 4.0.x-dev; varbase_content_base, varbase_media_base, varbase_seo_base, varbase_workflow_base 1.0.x-dev).

The README badge stays at 1.0.0-beta1, matching what the previous back-to-DEV on this branch (#3616610) did: it touched composer.json only.

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