bug(datepicker): VoiceOver on iOS Fails to Announce Day of Week in Angular Material Datepicker, Violating WCAG 1.3.1

### Is this a regression?

- [ ] Yes, this behavior used to work in the previous version

### The previous version in which this bug was not present was

_No response_

### Description

The Angular Material Datepicker does not announce the day of the week (which is present in the table header) when using VoiceOver on iOS. Currently, VoiceOver reads the selected date as “July 3rd, 2025, row X, column X,” but omits the associated day of the week.

This behavior does not meet [WCAG 2.1 Success Criterion 1.3.1: Info and Relationships (Level A)](https://www.w3.org/WAI/WCAG21/Understanding/info-and-relationships.html), as the relationship between the date and its corresponding day of the week is not conveyed to assistive technologies.

### Reproduction

Steps to Reproduce

1. Enable VoiceOver via Settings > Accessibility > VoiceOver
2. Open Safari on an iOS device.
3. Navigate to the Angular Material Datepicker demo page:https://material.angular.dev/components/datepicker/overview
4. Open the datepicker by selecting any of the date input fields.
5. Use VoiceOver to navigate through the calendar and select a date.
6. The VoiceOver does not read the Day of the Week.


### Expected Behavior

VoiceOver should announce the full date, including the day of the week.

### Actual Behavior

VoiceOver only reads the date and position (e.g., "July 3rd, 2025, row X, column X") but does not announce the day of the week, which is visually present in the table header.

### Environment

- Angular: 18, 20
- CDK/Material: 18, 20
- Browser(s): Safari
- Operating System (e.g. Windows, macOS, Ubuntu): iOS

Bắt đầu với bản demo tổng quan về datepicker của Angular Material và tái hiện vấn đề bằng VoiceOver trong Safari trên iOS. Theo dõi hành vi trợ năng của datepicker đối với các ô lịch và tiêu đề bảng, sau đó xác minh rằng VoiceOver thông báo thứ trong tuần cùng với ngày đã chọn mà không làm mất thông tin hàng và cột hiện có.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.