Convert the procedural hooks to OOP hook classes in the Varbase Styleguide module

Problem/Motivation

The Varbase Styleguide module implements its hooks as procedural functions in varbase_styleguide.module. Drupal 11 provides object-oriented hooks via the #[Hook] attribute (change record), which are autoloaded and support dependency injection.

Steps to reproduce

Review varbase_styleguide.module: the hooks are procedural functions.

Proposed resolution

Move the hook_page_attachments() and hook_help() implementations into an object-oriented hook class Drupal\varbase_styleguide\Hook\VarbaseStyleguideHooks using the #[Hook] attribute, with the current route match, module handler, filter plugin manager and config factory injected via the constructor. The large hook_styleguide_alter() implementation (which renders demo content and embeds a large static markup template) and its render helpers are kept procedural to keep this change focused and low-risk.

Remaining tasks

• ✅ Add src/Hook/VarbaseStyleguideHooks.php (page_attachments + help)
• ✅ Reduce varbase_styleguide.module
• ➖ Keep hook_styleguide_alter() and render helpers procedural
• ✅ Reviewed by a human
• ✅ Release varbase-9.2.0, varbase_styleguide-9.2.0

User interface changes

None.

API changes

None. Standard hooks invoked by core only; see the OOP hooks change record.

Data model changes

None.

Release notes snippet

Converted the Varbase Styleguide hook_page_attachments() and hook_help() implementations to a Drupal 11 object-oriented hook class.

Release notes snippet

• task: #3608329 Convert the procedural hooks to OOP hook classes in the Varbase Style Guide module