🎨 Palette: Add confirmation dialog to 'Clear All' favorites button

[kastnerp]

What

Added an inline confirmation dialog to the "Clear All" favorites button in the FavoritesPanel.

Why

Clearing favorites is a destructive action that previously happened instantly upon click. This caused potential frustration if users clicked it accidentally. The confirmation step requires a second click to explicitly confirm, reducing the chance of accidental data loss.

Before/After

Before: Clicking "Clear All" immediately erased all favorites.
After: Clicking "Clear All" transforms the button into a confirmation state ("Sure? Yes / No"). Clicking "Yes" performs the clear, while clicking "No" cancels the action.

Accessibility

• Added aria-label="Confirm clear all favorites" to the "Yes" button.
• Added aria-label="Cancel clear all favorites" to the "No" button.
• Focused the confirmation buttons via proper semantic markup to ensure screen readers understand the context of the actions.

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PR created automatically by Jules for task 1038747931730572315 started by @kastnerp

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