keymap editor: Refine how we display matching keystrokes (#35796)

| Before | After |
|--------|--------|
| <img width="1092" height="528" alt="CleanShot 2025-08-07 at 10  54
42@2x"
src="https://github.com/user-attachments/assets/8b0a3b50-e1d1-4763-824c-2b419df430fc"
/> | <img width="1096" height="580" alt="CleanShot 2025-08-07 at 11  29
47@2x"
src="https://github.com/user-attachments/assets/bd484655-90a6-46fe-91ef-c9c8d2ab93bc"
/> |

Release Notes:

- N/A

crates/ui_input/src/ui_input.rs

@@ -168,7 +168,7 @@ impl Render for SingleLineInput {
                     .py_1p5()
                     .flex_grow()
                     .text_color(style.text_color)
-                    .rounded_lg()
+                    .rounded_sm()
                     .bg(style.background_color)
                     .border_1()
                     .border_color(style.border_color)