docs(common): fix activeVersion onChange JSDoc wording

The onChange event comment said "activate version changed" while the
property is activeVersion. Clarify that the event fires when the active
Unicode version changes.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/common/services/Services.ts

@@ -350,7 +350,7 @@ export interface IUnicodeService {
   readonly versions: string[];
   /** Currently active version. */
   activeVersion: string;
-  /** Event triggered, when activate version changed. */
+  /** Event triggered when the active version changes. */
   readonly onChange: IEvent<string>;
 
   /**