Move the LoadingLabel component to the UI crate (#33893)

So we can use it in other places and don't require them to depend on the
`agent_ui`. This PR also renames it from `AnimatedLabel` to
`LoadingLabel`.

Release Notes:

- N/A

crates/ui/src/components/label.rs

@@ -1,7 +1,9 @@
 mod highlighted_label;
 mod label;
 mod label_like;
+mod loading_label;
 
 pub use highlighted_label::*;
 pub use label::*;
 pub use label_like::*;
+pub use loading_label::*;

crates/ui/src/components/label/loading_label.rs

@@ -0,0 +1,121 @@
+use crate::prelude::*;
+use gpui::{Animation, AnimationExt, FontWeight, pulsating_between};
+use std::time::Duration;
+
+#[derive(IntoElement)]
+pub struct LoadingLabel {
+    base: Label,
+    text: SharedString,
+}
+
+impl LoadingLabel {
+    pub fn new(text: impl Into<SharedString>) -> Self {
+        let text = text.into();
+        LoadingLabel {
+            base: Label::new(text.clone()),
+            text,
+        }
+    }
+}
+
+impl LabelCommon for LoadingLabel {
+    fn size(mut self, size: LabelSize) -> Self {
+        self.base = self.base.size(size);
+        self
+    }
+
+    fn weight(mut self, weight: FontWeight) -> Self {
+        self.base = self.base.weight(weight);
+        self
+    }
+
+    fn line_height_style(mut self, line_height_style: LineHeightStyle) -> Self {
+        self.base = self.base.line_height_style(line_height_style);
+        self
+    }
+
+    fn color(mut self, color: Color) -> Self {
+        self.base = self.base.color(color);
+        self
+    }
+
+    fn strikethrough(mut self) -> Self {
+        self.base = self.base.strikethrough();
+        self
+    }
+
+    fn italic(mut self) -> Self {
+        self.base = self.base.italic();
+        self
+    }
+
+    fn alpha(mut self, alpha: f32) -> Self {
+        self.base = self.base.alpha(alpha);
+        self
+    }
+
+    fn underline(mut self) -> Self {
+        self.base = self.base.underline();
+        self
+    }
+
+    fn truncate(mut self) -> Self {
+        self.base = self.base.truncate();
+        self
+    }
+
+    fn single_line(mut self) -> Self {
+        self.base = self.base.single_line();
+        self
+    }
+
+    fn buffer_font(mut self, cx: &App) -> Self {
+        self.base = self.base.buffer_font(cx);
+        self
+    }
+
+    fn inline_code(mut self, cx: &App) -> Self {
+        self.base = self.base.inline_code(cx);
+        self
+    }
+}
+
+impl RenderOnce for LoadingLabel {
+    fn render(self, _window: &mut Window, _cx: &mut App) -> impl IntoElement {
+        let text = self.text.clone();
+
+        self.base
+            .color(Color::Muted)
+            .with_animations(
+                "loading_label",
+                vec![
+                    Animation::new(Duration::from_secs(1)),
+                    Animation::new(Duration::from_secs(1)).repeat(),
+                ],
+                move |mut label, animation_ix, delta| {
+                    match animation_ix {
+                        0 => {
+                            let chars_to_show = (delta * text.len() as f32).ceil() as usize;
+                            let text = SharedString::from(text[0..chars_to_show].to_string());
+                            label.set_text(text);
+                        }
+                        1 => match delta {
+                            d if d < 0.25 => label.set_text(text.clone()),
+                            d if d < 0.5 => label.set_text(format!("{}.", text)),
+                            d if d < 0.75 => label.set_text(format!("{}..", text)),
+                            _ => label.set_text(format!("{}...", text)),
+                        },
+                        _ => {}
+                    }
+                    label
+                },
+            )
+            .with_animation(
+                "pulsating-label",
+                Animation::new(Duration::from_secs(2))
+                    .repeat()
+                    .with_easing(pulsating_between(0.6, 1.)),
+                |label, delta| label.map_element(|label| label.alpha(delta)),
+            )
+    }
+}

crates/ui/src/prelude.rs

@@ -25,7 +25,7 @@ pub use crate::{Button, ButtonSize, ButtonStyle, IconButton, SelectableButton};
 pub use crate::{ButtonCommon, Color};
 pub use crate::{Headline, HeadlineSize};
 pub use crate::{Icon, IconName, IconPosition, IconSize};
-pub use crate::{Label, LabelCommon, LabelSize, LineHeightStyle};
+pub use crate::{Label, LabelCommon, LabelSize, LineHeightStyle, LoadingLabel};
 pub use crate::{h_container, h_flex, v_container, v_flex};
 pub use crate::{
     h_group, h_group_lg, h_group_sm, h_group_xl, v_group, v_group_lg, v_group_sm, v_group_xl,