🎨 Palette: Add tooltip explaining disabled button state

[mapleleaflatte03]

💡 What
Added native title="Select items first" tooltips to the four disabled bulk action buttons (approve, stale, revoke, unresolved) in the Trust Ops UI.

🎯 Why
Previously, these buttons appeared disabled but offered no explanation as to why or how to enable them, leading to potential user confusion. The tooltip makes the prerequisite action (selecting items in the queue) explicitly clear.

📸 Before/After
Before: Hovering over the disabled buttons showed nothing.
After: Hovering over the disabled buttons shows a tooltip reading "Select items first".

♿ Accessibility
Improves accessibility by explicitly communicating the disabled state's reason to screen readers and visual users via the native title attribute, without relying on custom CSS.

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PR created automatically by Jules for task 1046949834138653116 started by @mapleleaflatte03

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