🎨 Palette: Enhance button feedback with dynamic labels and tooltips

[acebytes]

• 💡 What: Added dynamic text (e.g., 'Scanning...', 'Cleaning...') and .help() tooltips to main actions in the bottom bar.
• 🎯 Why: Explains to users why buttons are disabled and provides immediate feedback during asynchronous operations.
• 📸 Before/After: Before - static labels and no tooltips. After - dynamic labels and informative tooltips.
• ♿ Accessibility: Improves UX for all users and gives VoiceOver users better context about button states.

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PR created automatically by Jules for task 3357225645455641662 started by @acebytes

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