🎨 Palette: Add accessible labels to text share popover buttons

[hadsern]

💡 What: Added aria-label to the copy, X (Twitter), and link share buttons in the TextSharePopover component. Also explicitly hid the decorative SVGs from screen readers using aria-hidden="true".
🎯 Why: Icon-only buttons lacking accessible names are problematic for screen reader users. This ensures the purpose of the share buttons is clearly communicated to assistive technologies.
📸 Before/After: No visual change.
♿ Accessibility: Improved screen reader support for the share popover component by providing explicit textual names for icon-only interactive elements and hiding redundant visual SVG data.

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PR created automatically by Jules for task 10054301077593028154 started by @hadsern

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