Remove Sizzle selector compatibility helper and jQuery selector fallback in Drupal 12

Parent issue: https://www.drupal.org/node/3568777

Removal plan for Drupal 12

1. Delete `core/misc/sizzle-deprecation.js`.
2. Remove `misc/sizzle-deprecation.js` from `drupal.ajax` in `core/core.libraries.yml`.
3. Remove all calls to `Drupal.deprecateSizzleSelector(...)`.
4. Replace each removed call with a direct selector approach:
- If jQuery object is still required for chain/method calls: `$(response.selector)`.
- If only one DOM node is required: `document.querySelector(response.selector)`.
5. Remove any remaining deprecation-specific message text for Sizzle selector detection.

Files to update

- `core/core.libraries.yml`
- `core/misc/ajax.js`
- `core/modules/views_ui/js/ajax.js`

Acceptance criteria

- `Drupal.deprecateSizzleSelector` no longer exists in core.
- `core/misc/sizzle-deprecation.js` is removed.
- No `Drupal.deprecateSizzleSelector(` usages remain in the codebase.
- Related JavaScript tests are updated and passing.