Remove the never-applied base recipes and stop shipping the Varbase demo content in RightUp

Problem/Motivation

RightUp requires two Varbase recipes in composer.json that its own recipe.yml never applies:

• drupal/varbase_dev_base — development tooling. Not in the recipes: list, so nothing here applies it. Neither Educare nor Horizon Aid requires it.
• drupal/varbase_recipes — not in the recipes: list either. It is still installed, because drupal/varbase_admin_base requires it, so dropping the direct requirement changes nothing about what ends up on disk.

This is the same cleanup already done on the other site templates: Varbase Starter #3621334, Educare #3621335 and Horizon Aid #3621336 each dropped the base recipes they required but never applied. The packages differ per template; what is common is the rule that a site template should not require a recipe it does not apply.

The point of the rule is Drupal CMS. A site template has to resolve on Composer's default minimum-stability: stable, and every extra requirement is one more package whose release state has to be right for no benefit. Carrying a requirement that is never applied is pure risk.

Measured on 1.0.x today: RightUp requires 15 varbase_* packages and applies 13 of them. Horizon Aid, after its own cleanup, requires 13 and applies 13.

Steps to reproduce

1. Compare the drupal/varbase_* entries in composer.json with the recipes: list in recipe.yml.
2. varbase_dev_base and varbase_recipes appear only in the first.

Proposed resolution

Remove drupal/varbase_dev_base and drupal/varbase_recipes from composer.json. No change to recipe.yml, because neither is referenced there.

A developer who wants the development tooling on a RightUp site can still require drupal/varbase_dev_base in the project root, which is where a development-only dependency belongs.

Also: stop shipping the Varbase demo content

Unlike the two above, varbase_demo_content is in RightUp's recipes: list, so this part is a deliberate behaviour change rather than a cleanup: a new RightUp site no longer gets the generic Varbase demo content. RightUp is the media / news / magazine template and ships its own content, so the generic Varbase demo set does not belong in it. Horizon Aid already does not require it.

An existing site is unaffected. Recipes apply once, so content already created stays as it is.

It comes out of both recipe.yml and composer.json, since it is genuinely applied.

Remaining tasks

• ✅ File an issue
• ✅ Addition/Change/Update/Fix
• ❌ Testing to ensure no regression
• ❌ Reviewed by a human
• ❌ Code review by maintainers
• ❌ Release

User interface changes

• A new RightUp site no longer gets the generic Varbase demo content. The other two packages were never applied, so they change nothing.

API changes

• RightUp no longer requires drupal/varbase_dev_base. drupal/varbase_recipes still arrives through drupal/varbase_admin_base.

Data model changes

• None.

Release notes snippet

• Remove the two Varbase recipes RightUp required but never applied, matching the cleanup already done on the other site templates.
• Stop shipping the generic Varbase demo content. RightUp ships its own content.