Fix circular reference issue between EditPredictionButton and PopoverMenuHandle

[feeiyu]

Closes #ISSUE

While working on issue #40906, I discovered that RemoteClient was not being released after the remote project closed.
Analysis revealed a circular reference between EditPredictionButton and PopoverMenuHandle.

Dependency Chain: RemoteClient → Project → ZetaEditPredictionProvider → EditPredictionButton ↔ PopoverMenuHandle

a) EditPredictionButton hold the reference of PopoverMenuHandle

zed/crates/zed/src/zed.rs

Lines 386 to 394 in 5f82264

	let edit_prediction_button = cx.new(|cx| {
	edit_prediction_button::EditPredictionButton::new(
	app_state.fs.clone(),
	app_state.user_store.clone(),
	edit_prediction_menu_handle.clone(),
	app_state.client.clone(),
	cx,
	)
	});

b) PopoverMenuHandle hold the reference of Fn which capture Entity<EditPredictionButton>

zed/crates/edit_prediction_button/src/edit_prediction_button.rs

Lines 382 to 389 in 5fc5498

	let this = cx.entity();
	let mut popover_menu = PopoverMenu::new("zeta")
	.menu(move |window, cx| {
	Some(this.update(cx, |this, cx| this.build_zeta_context_menu(window, cx)))
	})
	.anchor(Corner::BottomRight)
	.with_handle(self.popover_menu_handle.clone());

zed/crates/ui/src/components/popover_menu.rs

Lines 376 to 384 in a9bc890

	if let Some(trigger_handle) = self.trigger_handle.take()
	&& let Some(menu_builder) = self.menu_builder.clone()
	{
	*trigger_handle.0.borrow_mut() = Some(PopoverMenuHandleState {
	menu_builder,
	menu: element_state.menu.clone(),
	on_open: self.on_open.clone(),
	});
	}

Release Notes:

• N/A

[SomeoneToIgnore]

Superb, thank you so much for all the context and a fix.

I've found a fixed a few of these myself, so I suspect this might not be the last one around.
Not yet sure what to do about a systematic way to fix this, but any other similar fixes are very welcome.

[feeiyu]

Perhaps we could check if key objects, such as Project/Workspace, are properly released after the project closure?

[SomeoneToIgnore]

after the project closure

Workspace isn't necessary going to be released, as technically, workspace == window and can be reused.
But overall, the "after the windows closure" idea seems viable to me.