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

Problem/Motivation

Varbase Editor currently implements its hooks as procedural functions in varbase_editor.module. Drupal 11 provides object-oriented hooks via the #[Hook] attribute (see the OOP hooks change record), which are autoloaded, easier to test, and support dependency injection. The procedural implementations of hook_editor_js_settings_alter(), hook_library_info_alter() and hook_filter_info_alter() in the module should be converted to the new OOP hook pattern.

Steps to reproduce

N/A — this is a code-quality refactoring task, not a defect. To see the current state:

1. Open varbase_editor.module.
2. Note that hook_editor_js_settings_alter(), hook_library_info_alter() and hook_filter_info_alter() are implemented procedurally rather than as OOP #[Hook] methods.

Proposed resolution

Move the procedural hook implementations (hook_editor_js_settings_alter, hook_library_info_alter, hook_filter_info_alter) into a new object-oriented hook class \Drupal\varbase_editor\Hook\VarbaseEditorHooks, using the #[Hook] attribute, with the module handler injected via the constructor. The .module file is reduced to its @file docblock.

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
• ✅ Reviewed by a human
• ✅ Code review by maintainers
• ✅ Full testing and approval
• ✅ Credit contributors
• ✅ Review with the product owner
• ✅ Update Release Notes
• ✅ Release varbase-9.2.0, varbase_editor-9.2.14

User interface changes

• N/A — internal refactor only, no user-facing UI change.

API changes

• None. These are standard hooks invoked by Drupal core only; converting them to the OOP #[Hook] pattern (https://www.drupal.org/node/3442349) does not change any public API or hook contract.

Data model changes

• N/A

Release notes snippet

• task: #3608324 Convert the procedural hooks to OOP hook classes in the Varbase Editor module