Add an animation to the LSP checking indicator (#9463)

Spinner go spinny.

Extra thanks to @kvark for helping me with the shaders.



https://github.com/zed-industries/zed/assets/2280405/9d5f4f4e-0d43-44d2-a089-5d69939938e9


Release Notes:

- Added a spinning animation to the LSP checking indicator

---------

Co-authored-by: Dzmitry Malyshau <kvark@fastmail.com>

crates/diagnostics/src/items.rs

@@ -1,8 +1,10 @@
+use std::time::Duration;
+
 use collections::HashSet;
 use editor::Editor;
 use gpui::{
-    rems, EventEmitter, IntoElement, ParentElement, Render, Styled, Subscription, View,
-    ViewContext, WeakView,
+    percentage, rems, Animation, AnimationExt, EventEmitter, IntoElement, ParentElement, Render,
+    Styled, Subscription, Transformation, View, ViewContext, WeakView,
 };
 use language::Diagnostic;
 use lsp::LanguageServerId;
@@ -66,7 +68,17 @@ impl Render for DiagnosticIndicator {
             Some(
                 h_flex()
                     .gap_2()
-                    .child(Icon::new(IconName::ArrowCircle).size(IconSize::Small))
+                    .child(
+                        Icon::new(IconName::ArrowCircle)
+                            .size(IconSize::Small)
+                            .with_animation(
+                                "arrow-circle",
+                                Animation::new(Duration::from_secs(2)).repeat(),
+                                |icon, delta| {
+                                    icon.transform(Transformation::rotate(percentage(delta)))
+                                },
+                            ),
+                    )
                     .child(
                         Label::new("Checking…")
                             .size(LabelSize::Small)