docs: add missing prop to kapa (#12934)

* docs: add missing prop to kapa

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www/packages/docs-ui/src/providers/AiAssistant/index.tsx

@@ -185,6 +185,7 @@ export const AiAssistantProvider = ({
           onQuerySubmit: () => setPreventAutoScroll(false),
         },
       }}
+      userTrackingMode="cookie"
     >
       <AiAssistantInnerProvider
         {...props}