Screen Reader Announces Unnecessary Text "Microsoft.Maui.Controls.Platform.ItemTemplateContext" on Tasks Checkbox Navigation.: A11y_.NET MAUI SDKs_Task_Screenreader

### Github Tags:
#A11yTCS; #A11yMAS; #WCAG4.1.2; #A11ySev3; #ScreeReader; #E2E_.NET MAUI SDKs_Win32_Jul2026; #DesktopApp; #FTP; #.NET MAUI SDKs; #NameRoleValue; #a11ydb-field-name-extra; #ALLACCTEST;

### Issue Subcategory:
Form field name has extra information

### User Experience:
Screen reader users may have difficulty understanding or completing the field when its name includes unrelated text

### Repro Steps:
Open Maui sample template app > Tasks> Observed the issue.

### Actual Result:
When navigating to the Tasks checkbox list using a screen reader, the screen reader initially announces the irrelevant text "Microsoft.Maui.Controls.Platform.ItemTemplateContext" for every checkbox item. Upon pressing the Tab key again, the screen reader correctly announces the checkbox label and its state

### Expected Result:
Screen reader should directly announce the checkbox's accessible name and state and not unnecessary information.

### How to Fix:
Keep the field's accessible name focused on the field label. Move instructions, requirements, and error text to descriptions associated with `aria-describedby` instead of including them in the name.

### Environment details:
Application Name: .NET MAUI SDKs
OS: Windows 11 Enterprise Insider Preview 26300.8276

### Note:
"Contact [CAI Accessibility Support Channel](https://teams.microsoft.com/l/channel/19:DeCtYeREyQHw5jYsz9PPc3hpVw48m-tOlTkQ1jEn0eM1%40thread.tacv2/CAI%20Accessibility%20Support%20Channel?groupId=f5eb428c-9e6e-4c16-8143-33fe3961a9ae&tenantId=72f988bf-86f1-41af-91ab-2d7cd011db47) for Accessibility queries on design, development, test, usability or any processes"
Check out Accessibility Insights! - Identify accessibility bugs before check-in and make bug fixing faster and easier.

### Attachment:

https://github.com/user-attachments/assets/acb45169-944a-49af-9d28-57526fe1f005

Start by opening the MAUI sample template app and navigating to Tasks with a screen reader. Trace how the checkbox list exposes each item's accessible name and state, then compare the first announcement with the announcement after pressing Tab. Done means the irrelevant Microsoft.Maui.Controls.Platform.ItemTemplateContext text is no longer announced and the checkbox label and state are announced directly.

Written by the indexing model from the issue text.