fix(frontend): prevent submit during IME composition (#1562)

frontend/src/components/ai-elements/prompt-input.tsx

@@ -34,6 +34,7 @@ import {
   SelectTrigger,
   SelectValue,
 } from "@/components/ui/select";
+import { isIMEComposing } from "@/lib/ime";
 import { cn } from "@/lib/utils";
 import type { ChatStatus, FileUIPart } from "ai";
 import {
@@ -833,7 +834,7 @@ export const PromptInputTextarea = ({
 
   const handleKeyDown: KeyboardEventHandler<HTMLTextAreaElement> = (e) => {
     if (e.key === "Enter") {
-      if (isComposing || e.nativeEvent.isComposing) {
+      if (isIMEComposing(e, isComposing)) {
         return;
       }
       if (e.shiftKey) {