Adding debounce to self.param.update

[ahuang11]

I would like a built-in mechanism in the self.param.update method (or similar) that supports debouncing. https://www.geeksforgeeks.org/debouncing-in-javascript/

Example:

1. The code waits for 2 seconds before showing the loading icon.
2. If the process completes or the event resolves within those 2 seconds, the icon is never shown.
3. If the process doesn't complete, the icon appears after the delay, signaling that something is still loading.

This feature could be particularly useful for applications with frequent, rapid user interactions that trigger parameter updates (e.g., sliders or live data streams). It would improve the UX by removing flicker.

Use case would be linking widgets with self.state.param.busy, but at the current moment it could cause flickering:
holoviz/lumen#783 (comment)

I think it would be implemented here https://github.com/holoviz/param/blob/main/param/parameterized.py#L2297-L2357

[hoxbro]

I don't think this functionality should live in Param. I do think we should have some way to make the busy toggle not flicker on/off with a debounce, though I think this functionality should live in Panel.