Improve component accessibility with aria attributes

[LeonarddeR]

As a blind blazor user, I stumbled upon this component and am really impressed by its intuitiveness. Unfortunately it had some accessibility issues, which this pr aims to solve.

• The grid role is now set on the table element, as these tables are really pretty interactive in their ability to sort/filter. Keyboard accessibility would be neat, but that's out of scope for now
• Selected rows get the aria-selected attribute
• Page navigation links that couldn't be navigated get the aria-disabled attribute
• Detail view and filter view expand/collapse toggles get aria-expanded true or false, respectively
• The fancy emoji shown for collapse/expand and filter toggles have been hidden from screen readers, as they aren't very descriptive. Instead, the filter toggle now tells the screen reader user whether a filter has been applied.
• Set the scope attribute on the main table headers
• Aria-sort is set for the sort column, either ascending or descending
• The search role is added to the search bar

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!

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[IvanJosipovic]

Thank you for this PR. I must admit that accessibility is not an area that I have much exposure in. I will try to keep it in mind for future additions.