Initialize Varbase Media Assets recipe for default demo media content

Problem/Motivation

We need to create a new Varbase recipe called Varbase Media Assets to provide default demo media assets for all Varbase Media Types. This recipe will replace the content functionality previously provided by the varbase_media_demo module, transitioning from a traditional Drupal module to a modern Drupal recipe approach.

The recipe will provide pre-configured media entities (images, videos, documents) that are essential for:

• Development environments
• Testing and QA
• Demo sites and presentations
• Quick prototyping

Proposed resolution

Create a new recipe project at drupal/varbase_media_assets with the following structure:

• recipe.yml - Recipe definition following Varbase patterns
• composer.json - Project metadata with dependencies on Drupal Core ~11.3.0 and Varbase Media Base 11.0.x-dev
• content/file/ - File entities (39 YML files) and media asset files (38 images/videos)
• content/media/ - Media entities (42 YML files) for all Varbase Media Types which are inline with Drupal CMS
• .gitlab/ - Issue and merge request templates following Varbase standards
• README.md - Documentation for installation and usage
• logo.png - Varbase branding

Key changes from varbase_media_demo module:

• Content-only recipe (no config/install or config/optional directories)
• Removed field_media_in_library field from all media entities
• Removed field_media_cover_image field and associated cover image assets
• Modern recipe-based approach instead of traditional module

Remaining tasks

• ✅ File an issue about this project
• ✅ Addition/Change/Update/Fix to this project
• ✅ Testing to ensure no regression
• ✅ Automated unit/functional testing coverage
• ✅ Developer Documentation support on feature change/addition
• ➖ User Guide Documentation support on feature change/addition
• ➖ UX/UI designer responsibilities
• ➖ Accessibility and Readability
• ✅ Code review from 1 Varbase core team member
• ✅ Full testing and approval
• ✅ Credit contributors
• ✅ Review with the product owner
• ✅ Update Release Notes
• ❌ Release varbase-11.0.0-alpha1, varbase_starter-1.0.0-alpha1, varbase_media_assets-1.0.0-alpha1

User interface changes

• N/A

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• feat: #3570118 Initialize Varbase Media Assets recipe for default demo media content