🎨 Palette: Add tooltip explaining disabled button state

[mapleleaflatte03]

💡 What: Added a native tooltip (title attribute) explaining why the bulk-action buttons (approve, stale, revoke, unresolved) are disabled on the Trust Ops page. The tooltip says "Select items to enable bulk actions" and is dynamically removed by JavaScript when the buttons become active.

🎯 Why: When users see disabled buttons, it's often unclear what action they need to take to enable them. Providing context via a tooltip makes the interface more intuitive and reduces friction, guiding the user to select items first.

📸 Before/After:
Before: Disabled buttons provided no explanation.
After: Hovering over disabled buttons shows a tooltip: "Select items to enable bulk actions".

♿ Accessibility: Improves accessibility by clearly communicating the required state (item selection) to interact with the bulk-action controls. Native HTML title attributes are supported by most assistive technologies for disabled controls.

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PR created automatically by Jules for task 18430792818653080979 started by @mapleleaflatte03

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