fix: return real message id from chat_send so editing fresh messages works

ui/src/api.ts

@@ -188,7 +188,8 @@ export const api = {
     invoke<void>("deploy_model", { modelId, params }),
   engineStop: () => invoke<void>("engine_stop"),
   engineStatus: () => invoke<EngineStatus>("engine_status"),
-  chatSend: (payload: ChatSendPayload) => invoke<string>("chat_send", { payload }),
+  chatSend: (payload: ChatSendPayload) =>
+    invoke<{ conversation_id: string; message_id: string }>("chat_send", { payload }),
   regenerateMessage: (
     conversationId: string,
     messageId: string,

ui/src/pages/ChatPage.tsx

@@ -219,21 +219,27 @@ export default function ChatPage() {
       await refreshConversations();
     }
 
+    const tempUserId = `user-${Date.now()}`;
     setMessages((prev) => [
       ...prev,
-      { id: `user-${Date.now()}`, role: "user", content, images },
+      { id: tempUserId, role: "user", content, images },
       { id: `assistant-${Date.now()}`, role: "assistant", content: "", streaming: true },
     ]);
     setStreaming(true);
 
     try {
-      await api.chatSend({
+      const result = await api.chatSend({
         conversation_id: convId,
         model_id: selectedModelId,
         content,
         params,
         images,
       });
+      if (result?.message_id) {
+        setMessages((prev) =>
+          prev.map((m) => (m.id === tempUserId ? { ...m, id: result.message_id } : m)),
+        );
+      }
     } catch (e) {
       setStreaming(false);
       setError(String(e));