Fix AI stream by returning stream.value directly from Server Actions.

createStreamableValue must be created and returned in the action itself; wrapping in { data } or a helper return caused production RSC serialization errors.

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

app/actions/combined.ts

@@ -1,6 +1,7 @@
 "use server";
 
-import { streamAIResponse } from "@/lib/ai/stream";
+import { createStreamableValue } from "ai/rsc";
+import { pumpAIStream } from "@/lib/ai/stream";
 import {
   calculateBazi,
   formatBaziForPrompt,
@@ -69,7 +70,9 @@ export async function getCombinedAnswer(input: CombinedInput) {
     }
   }
 
-  return streamAIResponse(
+  const stream = createStreamableValue<string>();
+  pumpAIStream(
+    stream,
     COMBINED_SYSTEM_PROMPT,
     `【人和 · 八字排盘】
 出生地：${input.birthPlaceName}
@@ -81,4 +84,5 @@ ${hexagramText}
 【问事】
 ${input.question}`,
   );
+  return stream.value;
 }