docs: mention Angular CDK A11Y in accessibility guidance

Author: aminesbdev

skills/dev-skills/angular-developer/SKILL.md

@@ -99,6 +99,7 @@ When formatting values in templates, creating custom pipes, or reusing pipe-like
 When building accessible Angular applications and components, consult the following reference:
 
 - **Accessibility**: Semantic HTML, ARIA attributes, keyboard navigation, focus management, forms, dialogs, and accessibility testing. Read [accessibility.md](references/accessibility.md)
+- **Angular CDK A11Y**: Use `@angular/cdk/a11y` for advanced focus management, live announcements, and accessibility helpers. Read [accessibility.md](references/accessibility.md)
 - **Angular Aria Components**: Building headless, accessible components (Accordion, Listbox, Combobox, Menu, Tabs, Toolbar, Tree, Grid) and styling ARIA attributes. Read [angular-aria.md](references/angular-aria.md)
 
 ## Routing

skills/dev-skills/angular-developer/references/accessibility.md

@@ -94,3 +94,11 @@ This reference describes Angular accessibility best practices for semantic marku
 - Use `@angular/aria` for accessible widget patterns instead of reinventing ARIA logic.
 - When writing reusable components or libraries, expose accessible API surface and document required labels and roles.
 - Keep the accessibility implementation in sync with component state and Angular reactivity.
+
+## 12. Angular CDK A11Y
+
+- Use `@angular/cdk/a11y` for advanced accessibility helpers that complement native semantics and ARIA.
+- `LiveAnnouncer`, `CdkAriaLive`, and `announce()` help announce dynamic content updates to screen readers.
+- `FocusMonitor`, `FocusTrap`, and `FocusKeyManager` provide robust focus handling for overlays, dialogs, menus, and custom controls.
+- `CdkObserveContent` and the `A11yModule` help keep application state in sync with assistive technology.
+- Refer to the Angular CDK A11Y overview: https://material.angular.dev/cdk/a11y/overview