Add standard Drupal heading for the Textarea template with Theme override for a textarea #type form element

Problem/Motivation

No standard comments in the textarea.html.twig file
No linking to the used varbase_components:textarea info or README.md file.
#3381665: Add missing wrapper and properties for the Textarea component

Proposed resolution

Have the standard comments
Link to Textarea README.md file

{#
/**
 * @file
 * Theme override for a 'textarea' #type form element.
 *
 * Available variables
 * - wrapper_attributes: A list of HTML attributes for the wrapper element.
 * - attributes: A list of HTML attributes for the <textarea> element.
 * - resizable: An indicator for whether the textarea is resizable.
 * - required: An indicator for whether the textarea is required.
 * - value: The textarea content.
 *
 *
 * Used Varbase Components:
 * - textarea: Text area type form element.
 *   https://github.com/Vardot/varbase_components/blob/2.0.x/components/atoms/textarea/README.md
 *
 * @see template_preprocess_textarea()
 */
#}
{% include 'varbase_components:textarea' %}

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
• ✅ 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 and Update Helper on new feature change/addition
• ✅ Release Varbase 10.0.0-beta1, vartheme_bs5-3.0.0-alpha12

Varbase update type

• ✅ No Update
• ➖ Optional Update
• ➖ Forced Update
• ➖ Forced Update if Unchanged

User interface changes

• N/A

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• Issue #3382141: Added standard Drupal heading for the Textarea template with Theme override for a textarea #type form element