🎨 Palette: [UX improvement] Enhance accessibility of TextSharePopover buttons

[hadsern]

💡 What:

Enhanced the accessibility and keyboard navigation of the TextSharePopover component.

🎯 Why:

The three icon-only buttons (Copy text, Share on X, Copy page link) lacked descriptive ARIA labels, making them invisible or confusing to screen reader users. They also lacked clear visual focus states, making them difficult to use for keyboard-only users. Redundant SVG announcements were also an issue.

📸 Before/After:

Before:

• Screen readers either didn't announce the buttons or tried to read raw SVG content.
• Tabbing to the buttons provided no visual indication of focus.

After:

• Screen readers correctly announce "Copy text" (or "Copied!"), "Share on X", and "Copy page link".
• Tabbing to the buttons clearly shows a golden focus ring (ring-frc-gold).
• SVGs are hidden from screen readers.

♿ Accessibility:

• Added dynamic aria-label to the Copy button (matches its title).
• Added static aria-labels to the X and Link buttons.
• Added aria-hidden="true" to all inner <svg> elements.
• Added Tailwind focus-visible classes to all three buttons to ensure a visible focus ring on keyboard focus, without interfering with mouse click states.

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PR created automatically by Jules for task 12889663548340390446 started by @hadsern

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