Style language server name in completion menu

Omit in buffers with one or zero running language servers with the
capability to provide completions

Co-Authored-By: Antonio Scandurra <antonio@zed.dev>

styles/src/style_tree/editor.ts

@@ -205,6 +205,9 @@ export default function editor(): any {
                 match_highlight: foreground(theme.middle, "accent", "active"),
                 background: background(theme.middle, "active"),
             },
+            server_name_container: { padding: { left: 40 } },
+            server_name_color: text(theme.middle, "sans", "disabled", {}).color,
+            server_name_size_percent: 0.75,
         },
         diagnostic_header: {
             background: background(theme.middle),