🎨 Palette: [UX improvement] Add ARIA state attributes to NavMenu toggles

[secrooq]

💡 What

Added missing aria-expanded attributes to track the open/closed states of mobile hamburger, mobile profile, and user dropdown menus. Also added missing aria-labels to close buttons and toggles.

🎯 Why

Ensures that screen readers and other assistive technologies can accurately communicate the state of interactive components (open vs closed) and their purpose, providing a much more intuitive navigation experience.

📸 Before/After

(No visual changes; this is an accessibility enhancement under the hood).

♿ Accessibility

• Added aria-expanded={isMobileMenuOpen} and aria-label="Toggle Navigation Menu" to the main hamburger icon.
• Added aria-expanded={isMobileProfileOpen} and aria-label="Toggle Mobile Profile Menu" to the mobile user icon.
• Added aria-labels to the Close (X) buttons inside both mobile drawers.
• Added aria-expanded={isUserDropdownOpen} and aria-label="Toggle User Dropdown Menu" to the desktop profile widget.

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PR created automatically by Jules for task 13375938936793072497 started by @secrooq

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