fix (ui/svelte): send data to server (#1748)

Co-authored-by: Andrew Risse <andrewrisse@gmail.com>
Co-authored-by: Andrew Risse <52644157+andrewrisse@users.noreply.github.com>

Author: lgrammel

.changeset/blue-steaks-boil.md

@@ -0,0 +1,5 @@
+---
+'ai': patch
+---
+
+fix (ui/svelte): send data to server

packages/core/svelte/use-chat.ts

@@ -260,6 +260,7 @@ export function useChat({
       function_call,
       tools,
       tool_choice,
+      data,
     }: ChatRequestOptions = {},
   ) => {
     if (!message.id) {
@@ -269,6 +270,7 @@ export function useChat({
     const chatRequest: ChatRequest = {
       messages: get(messages).concat(message as Message),
       options,
+      data,
       ...(functions !== undefined && { functions }),
       ...(function_call !== undefined && { function_call }),
       ...(tools !== undefined && { tools }),