🎨 Palette: Add visual feedback to copy action in SupportApp

[schmug]

💡 What: Added an interactive "Copied!" state and a ✅ icon to the "Tell a friend" copy-to-clipboard action in the Support app.
🎯 Why: Background actions like navigator.clipboard.writeText are invisible to the user. Without explicit visual feedback, users are left wondering if the action succeeded, which leads to redundant clicks and uncertainty. This gives immediate and clear confirmation.
📸 Before/After: The "Copy link" text now changes to "Copied!" with a ✅ icon for 2 seconds when clicked.
♿ Accessibility: Provides necessary visual confirmation for an action that has no native feedback.

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PR created automatically by Jules for task 368155041140339136 started by @schmug

[google-labs-jules]

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