[feature: web-components] Update Radio/RadioGroup implementation to use ElementInternals

[chrisdholt]

Describe the issue:

This issue exists to track converting the web-component radio/radiogroup to use ElementInternals rather than the current FormAssociation behavior.

As part of this change, we should:

• Get the DOM for Radio/Radiogroup as clean and light as possible
• Strip as much duplication of observed ARIA attributes out of each control
• Ensure the control reads as expected from assistive technology
• Add tests to validate the control participates in form association as expected by the platform.

Note: In exploring this, we should look for opportunities to be more efficient and validate if there are ways to get more closely aligned to the platform with the move to ElementInternals.