kdb: Add min width 20px to Kdb. (#700)

<img width="358" alt="image"
src="https://github.com/user-attachments/assets/824a0cdd-e03b-49f4-bde6-b77ae0ab48cd"
/>

crates/story/src/text_story.rs

@@ -238,6 +238,7 @@ impl Render for TextStory {
                         .child(Kbd::new(Keystroke::parse("cmd-ctrl-t").unwrap()))
                         .child(Kbd::new(Keystroke::parse("escape").unwrap()))
                         .child(Kbd::new(Keystroke::parse("backspace").unwrap()))
+                        .child(Kbd::new(Keystroke::parse("/").unwrap()))
                         .child(Kbd::new(Keystroke::parse("enter").unwrap())),
                 ),
             )

crates/ui/src/kbd.rs

@@ -60,7 +60,9 @@ impl RenderOnce for Kbd {
             .bg(cx.theme().background)
             .py_0p5()
             .px_1()
-            .rounded_md()
+            .min_w_5()
+            .text_center()
+            .rounded_sm()
             .line_height(relative(1.))
             .text_xs()
             .child(Self::format(&self.stroke))