Fix linux zeta modifiers display (#24764)

Improves rendering of Zeta keybind shortcuts on Linux

Before:

![image](https://github.com/user-attachments/assets/9b6a61f7-dade-480f-a864-acdcede05957)

After: (with muting modifier changes merged)

![image](https://github.com/user-attachments/assets/dd616d29-ac2e-4c8b-bf9b-5d74f8e4f1c4)


Release Notes:

- N/A

---------

Co-authored-by: Michael <michael@zed.dev>
Co-authored-by: Agus <agus@zed.dev>

crates/util/src/util.rs

@@ -787,6 +787,28 @@ impl<'a> PartialOrd for NumericPrefixWithSuffix<'a> {
     }
 }
 
+/// Capitalizes the first character of a string.
+///
+/// This function takes a string slice as input and returns a new `String` with the first character
+/// capitalized.
+///
+/// # Examples
+///
+/// ```
+/// use util::capitalize;
+///
+/// assert_eq!(capitalize("hello"), "Hello");
+/// assert_eq!(capitalize("WORLD"), "WORLD");
+/// assert_eq!(capitalize(""), "");
+/// ```
+pub fn capitalize(str: &str) -> String {
+    let mut chars = str.chars();
+    match chars.next() {
+        None => String::new(),
+        Some(first_char) => first_char.to_uppercase().collect::<String>() + chars.as_str(),
+    }
+}
+
 fn emoji_regex() -> &'static Regex {
     static EMOJI_REGEX: LazyLock<Regex> =
         LazyLock::new(|| Regex::new("(\\p{Emoji}|\u{200D})").unwrap());