🎨 Palette: Enhance calendar view selector accessibility

[endlessblink]

🎨 Palette: Enhance Calendar View Options and Selector Accessibility

💡 What:

• Added :aria-expanded to the "View options" popover trigger button.
• Restructured the minimal calendar view selector container (Day/Week/Month) with role="group" and aria-label="Calendar view".
• Added dynamic :aria-pressed bindings to the individual view mode buttons (Day, Week, Month) corresponding to their active states.
• Cleaned up boolean prop shorthand warnings.

🎯 Why:

• Custom segmented controls acting as view selectors were previously built with raw buttons and active classes, lacking semantic grouping and state exposure for screen readers.
• Adding :aria-pressed allows screen readers to natively announce which view mode is currently selected.
• Adding :aria-expanded to the popover trigger ensures screen reader users know when the view options menu is open or closed.

♿ Accessibility:

• Improved screen reader comprehension of custom segmented controls and toggle popovers by properly exposing interaction states.

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PR created automatically by Jules for task 7862601158573756603 started by @endlessblink

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