Provided HighContrast theme support for the Tools components and resolved screen reader issues.

[Indhumathy-Loganathan]

Description
This pull request focuses on accessibility enhancements across the Blazor Toolkit repository by resolving screen reader compatibility issues and introducing high contrast theme support. These updates improve the overall user experience for assistive technology users and strengthen compliance with accessibility standards.

Key Changes
Accessibility Improvements:

• Resolved screen reader issues identified in NVDA and Narrator across toolkit components - Improved screen reader announcements and content interpretation for assistive technology users - Updated accessibility implementation patterns to ensure better compatibility with modern screen readers - Enhanced keyboard and accessibility interactions to provide a more inclusive user experience - Addressed accessibility validation findings to improve standards compliance

High Contrast Theme Support:

• Added high contrast theme support across Blazor Toolkit components - Enhanced visual accessibility for users who rely on high contrast settings - Updated component styling to improve visibility, readability, and focus indication in high contrast mode - Ensured UI elements render correctly and remain accessible across supported contrast themes - Improved overall accessibility experience for users with visual impairments

Files Affected

• Blazor Toolkit source files
• Theme and styling files related to high contrast support
• Screen reader compatibility and accessibility implementation files
• Additional files updated to support accessibility compliance and user experience improvements

[github-actions]

CI Summary

Job	Status
bUnit (.NET 8 / 9 / 10)	✅ Passed
Playwright	✅ Passed
NuGet vulnerability scan	✅ Passed
ESLint security	✅ Passed
XSS / unsafe markup scan	✅ Passed

Overall: ✅ All checks passed