Animate Zeta button while generating completions (#22899)

Release Notes:

- N/A

Co-authored-by: Thorsten <thorsten@zed.dev>

crates/ui/src/components/button/icon_button.rs

@@ -22,6 +22,7 @@ pub struct IconButton {
     icon_size: IconSize,
     icon_color: Color,
     selected_icon: Option<IconName>,
+    alpha: Option<f32>,
 }
 
 impl IconButton {
@@ -33,6 +34,7 @@ impl IconButton {
             icon_size: IconSize::default(),
             icon_color: Color::Default,
             selected_icon: None,
+            alpha: None,
         };
         this.base.base = this.base.base.debug_selector(|| format!("ICON-{:?}", icon));
         this
@@ -53,6 +55,11 @@ impl IconButton {
         self
     }
 
+    pub fn alpha(mut self, alpha: f32) -> Self {
+        self.alpha = Some(alpha);
+        self
+    }
+
     pub fn selected_icon(mut self, icon: impl Into<Option<IconName>>) -> Self {
         self.selected_icon = icon.into();
         self
@@ -146,6 +153,7 @@ impl RenderOnce for IconButton {
         let is_selected = self.base.selected;
         let selected_style = self.base.selected_style;
 
+        let color = self.icon_color.color(cx).opacity(self.alpha.unwrap_or(1.0));
         self.base
             .map(|this| match self.shape {
                 IconButtonShape::Square => {
@@ -161,7 +169,7 @@ impl RenderOnce for IconButton {
                     .selected_icon(self.selected_icon)
                     .when_some(selected_style, |this, style| this.selected_style(style))
                     .size(self.icon_size)
-                    .color(self.icon_color),
+                    .color(Color::Custom(color)),
             )
     }
 }

crates/ui/src/components/popover_menu.rs

@@ -15,6 +15,28 @@ pub trait PopoverTrigger: IntoElement + Clickable + Toggleable + 'static {}
 
 impl<T: IntoElement + Clickable + Toggleable + 'static> PopoverTrigger for T {}
 
+impl<T: Clickable> Clickable for gpui::AnimationElement<T>
+where
+    T: Clickable + 'static,
+{
+    fn on_click(self, handler: impl Fn(&gpui::ClickEvent, &mut WindowContext) + 'static) -> Self {
+        self.map_element(|e| e.on_click(handler))
+    }
+
+    fn cursor_style(self, cursor_style: gpui::CursorStyle) -> Self {
+        self.map_element(|e| e.cursor_style(cursor_style))
+    }
+}
+
+impl<T: Toggleable> Toggleable for gpui::AnimationElement<T>
+where
+    T: Toggleable + 'static,
+{
+    fn toggle_state(self, selected: bool) -> Self {
+        self.map_element(|e| e.toggle_state(selected))
+    }
+}
+
 pub struct PopoverMenuHandle<M>(Rc<RefCell<Option<PopoverMenuHandleState<M>>>>);
 
 impl<M> Clone for PopoverMenuHandle<M> {