fix: restore mention keyboard shortcuts

src/components/ui/rich-text-editor.tsx

@@ -269,12 +269,10 @@ const TicketMentionExtension = Mention.extend({
     }
   },
   addKeyboardShortcuts() {
-    const mentionPrototype = Mention as unknown as {
+    // Reuse base Mention keyboard shortcuts when extending the extension.
-      prototype: { addKeyboardShortcuts?: (this: unknown) => unknown }
+    const parentShortcuts = (this as unknown as {
-    }
+      parent?: () => Record<string, (args: { editor: Editor }) => boolean>
-    const parentShortcuts = mentionPrototype.prototype.addKeyboardShortcuts?.call(this) as
+    }).parent?.()
-      | Record<string, (args: { editor: Editor }) => boolean>
-      | undefined
     const parent = parentShortcuts ?? {}
     return {
       ...parent,