chore: add comment explaining preventDefault behavior for Space key

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: zombieJ

src/BaseSelect/index.tsx

@@ -470,6 +470,7 @@ const BaseSelect = React.forwardRef<BaseSelectRef, BaseSelectProps>((props, ref)
 
     // Enter or Space opens dropdown (ARIA combobox: spacebar should open)
     if (isEnterKey || isSpaceKey) {
+      // Do not submit form when type in the input; prevent Space from scrolling page
       const isEditable = mode === 'combobox' || showSearch;
       if (!isEditable) {
         event.preventDefault();