Remove the Varbase Dev Base dependency from the Varbase Starter recipe composer.json

Problem/Motivation

The Varbase Starter recipe package requires drupal/varbase_dev_base (~1.0.0) in the require section of composer.json (line 26), but the recipe never applies it.

• Varbase Dev Base is a development recipe. Its own description: "A recipe to manage default development modules and configurations. Development Environment Modules, make sure to disable them in production."
• It installs dblog, views_ui, config_update_ui, devel, sdc_devel and reroute_email, and its Composer package additionally pulls drupal/storybook, drupal/stage_file_proxy, drupal/devel_entity_updates, drupal/config_ignore and drupal/config_update.
• The Starter recipe never applies it: the recipes: list in recipe.yml has 25 entries and none of them is varbase_dev_base. The package is required but unused, so every consumer of the site template pays for a development stack the recipe never applies.
• The project's own CI already says so. Around line 340 of .gitlab-ci.yml the test host does its own composer require drupal/varbase_dev_base (with the i18n, API, auth and AI bases), under the comment: "The copied varbase_project suites exercise the API / Auth / i18n / AI stacks, which the Varbase Starter recipe deliberately does not compose." CI adds the package itself and does not rely on the composer.json entry, so that entry contradicts the stated intent.

Steps to reproduce

1. Open composer.json on the 1.0.x branch of Varbase Starter and see "drupal/varbase_dev_base": "~1.0.0" in require (line 26).
2. Open recipe.yml and read the recipes: list: varbase_dev_base is not among its 25 entries.
3. Require drupal/varbase_starter in a project and observe that the development stack is pulled into the codebase while the recipe never applies it.

Proposed resolution

• Remove the single line "drupal/varbase_dev_base": "~1.0.0" from require in composer.json. Nothing else changes.
• CI impact: none. The composer require at around line 340 of .gitlab-ci.yml and the recipe-apply loop at around line 365 are self-contained and do not read this entry.
• Open question for whoever picks this up: tests/README.md mentions varbase_dev_base in the recipe list it documents. Check whether that line needs a matching update.
• Pair issue: #3621020: Add the Varbase Dev Base recipe to the Varbase Project Template composer.json, where the development recipe belongs.

Remaining tasks

• ✅ 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

User interface changes

• N/A

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• N/A