🎨 Palette: Add disabled cursor to action buttons

[jspann21]

💡 What: Added dynamic cursor-not-allowed Tailwind classes to the span wrappers of various disabled action buttons across the library UI (Add Books, Save Changes, Rescan, Open File, Hide, Delete).

🎯 Why: In our current setup, disabled buttons have pointer-events-none applied via the disabled:pointer-events-none utility class. This natively prevents any pointer events from being fired by the button, intrinsically disabling the CSS cursor-not-allowed style applied directly to the button itself. Users received no visual hover feedback that an action was disabled. To fix this, the disabled cursor state must be applied to the wrapper element instead.

📸 Before/After: Visual changes only noticeable via hover states. When hovering over disabled buttons, the cursor now changes to the 'not allowed' circle-slash indicator.

♿ Accessibility: Clearer visual communication of application state. Users who rely on hover feedback will easily recognize when an action is unavailable.

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PR created automatically by Jules for task 13268461503833705442 started by @jspann21

[google-labs-jules]

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