🎨 Palette: Add tooltips to icon-only buttons

[dlukt]

🎨 Palette: Add tooltips to icon-only buttons

💡 What: Added android:tooltipText to icon-only ImageButton and ImageView elements, perfectly matching their existing android:contentDescription.
🎯 Why: To enhance accessibility for sighted users on Android API 26+ devices. While contentDescription supports screen readers, tooltipText provides native visual feedback on hover (mouse/stylus) or long-press (touch), making the interface more discoverable and intuitive without relying on external documentation.
📸 Before/After: No major visual change immediately, but a small pop-up tooltip appears on hover/long-press on devices running Android Oreo (API 26) or higher.
♿ Accessibility: Direct improvement matching Android accessibility best practices. Older devices will safely ignore the attribute.

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PR created automatically by Jules for task 3915215734906060726 started by @dlukt

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