Unnecessary Tab Stop on Category Breakdown Doughnut Chart.: A11y_.NET MAUI SDKs_Task_Keyboard

### Github Tags:
#A11yTCS; #A11yUsable; #ScreeReader; #E2E_.NET MAUI SDKs_Win32_Jul2026; #DesktopApp; #FTP; #.NET MAUI SDKs; #FocusOrder; #a11ydb-static-in-tab-order; #ALLACCTEST;

### Issue Subcategory:
Illogical focus order

### User Experience:
Keyboard users encounter controls in an unexpected, confusing sequence that does not match the visual layout, and may also not match the programmatic ordering of content. These form fields may be reached out of order, causing uncertainty of input purpose or could result in data entry errors from the user do to the focused item not matching what they'd expect

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

### Actual Result:
When navigating using TAB or SHIFT+TAB, the keyboard focus lands on the Category Breakdown Doughnut Chart. After the chart receives focus, users must press TAB (or SHIFT+TAB) an extra time before focus moves to the next (or previous) interactive control. This introduces an unnecessary stop in the keyboard navigation sequence.

### Expected Result:
Keyboard focus should move directly to the next or previous interactive control without requiring an extra keystroke.

### How to Fix:
Ensure the programmatic ordering of focusable elements aligns with their visual ordering. Use CSS for visual positioning without changing the underlying DOM order. If the issue is specifically caused by positive `tabindex` values, log and remediate using the positive-tabindex bug type

### 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/9018538c-4a5f-4ec4-a137-3cbf92ba6bb5

Start by reproducing the issue in the Maui sample template app on Windows 11, using TAB and SHIFT+TAB around the Category Breakdown Doughnut Chart. Trace the chart's focus behavior and surrounding interactive controls; done means focus moves directly to the adjacent control without an unnecessary stop.

Written by the indexing model from the issue text.