🎨 Palette: Add tooltip and focus styles to Match All button

[jspann21]

💡 What: Added a native tooltip to the "Match All" button that explains why it is disabled (e.g. "No unresolved files to match", "Matching in progress..."). Additionally, added keyboard focus states (focus-visible:ring-2) to the button.
🎯 Why: Disabled buttons without explanations cause user frustration and confusion. By providing a tooltip, users immediately understand the context of the disabled state. The keyboard focus improvements ensure the component is properly accessible to keyboard navigation users.
📸 Before/After: The button now reveals a helpful tooltip when hovered in its disabled state, thanks to a wrapping span that captures pointer events, while the button itself ignores pointer events.
♿ Accessibility: Improved keyboard focus visibility and added contextual help for disabled interactive elements.

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PR created automatically by Jules for task 8950306659606646865 started by @jspann21

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