fix: dialog now uses global backdrop to eliminate that the overlay-panels remain interactive

[laszloilonka]

IDS-2234

Breaking Changes

1. The native <dialog> element is no longer used

The ids-dialog component no longer relies on the native HTML <dialog> element and has been migrated to Angular CDK Dialog.

Previous usage:

<dialog idsDialog>
  ...
</dialog>

New usage:

<ids-dialog>
  ...
</ids-dialog>

The ids-dialog component is now rendered inside an Angular CDK overlay instead of using the browser's native dialog implementation.

---

2. Native dialog APIs are no longer available

The following native HTMLDialogElement APIs are no longer supported:

• show()
• showModal()
• Native close() behavior
• Native cancel event
• Native close event
• ::backdrop CSS pseudo-element

Dialog opening and closing are now managed by Angular CDK Dialog.

---

3. Static dialogs are now internally implemented using Angular CDK Dialog

Static dialogs continue to support the same public API:

<ids-dialog #dialog="idsDialog">
  ...
</ids-dialog>

<button type="button" (click)="dialog.open()">
  Open dialog
</button>

However, the implementation has changed internally. Calling open() now creates an Angular CDK Dialog instance instead of invoking the native showModal() API.

This change improves compatibility with other Angular CDK overlay-based components such as selects, menus, autocomplete panels, and custom overlays.