🎨 Palette: Add tooltips explaining disabled button states

[jspann21]

💡 What: Added descriptive tooltips to the "Match All" (in Unresolved Files queue) and "Approve Match" (in Match Preview Modal) buttons when they are disabled.
🎯 Why: To prevent user confusion. When primary action buttons are disabled without explanation, users often don't know what state the app is in or what they need to do (e.g., waiting on a search, or needing to select a candidate first).
📸 Before/After: The buttons now show native tooltips explaining their exact disabled state, such as "Matching in progress...", "No unresolved files to match", or "Select a candidate to approve".
♿ Accessibility: By wrapping the disabled buttons in spans and applying disabled:pointer-events-none to the buttons, we allow pointer events (like hovering for native tooltips and displaying the cursor-not-allowed style) to function correctly, providing clear visual and text feedback.

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PR created automatically by Jules for task 9080446416516725660 started by @jspann21

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