Fix: Make dropdown radio and checkbox icons clickable (#1590)

[tirthraj01]

Summary of Changes

Closes #1590

• Dropdown Component: Moved <div className={styles.icon}> inside the <button> element so that the entire row, including the circular icon, is part of the interactive click target.
• Styles: Adjusted .option and .option button in styles.module.scss to expand the button to width: 100% and handle flex alignment and padding.
• Variant Type: Added support for "checkbox" variant alongside "radio" to properly reflect the multi-select nature of accessibility preferences.
• AccessibilitySettings: Updated variant from "radio" to "checkbox".

Verification

• Tested clicking directly on the circular radio/checkbox icon in the Accessibility Settings dropdown (toggles properly).
• Tested clicking on the text label.
• Tested the Language Selector dropdown to ensure no regressions.
• Verified keyboard navigation (Arrow keys, Space, Enter, Escape).