Save a local transcript

Write the transcript to soundElem.text on a complete message object while preserving all other message fields:

const updated = {
  ...message,
  soundElem: { ...message.soundElem, text: { text: transcript, translate: message.soundElem.text?.translate ?? {} } },
};
await openimsdk.setMessageLocalContent({ conversationID, message: updated });

This method does not perform a partial update. When the Promise resolves, the current device's local database has saved the value. It does not upload to the server, trigger a message event, or synchronize the transcript to other users or devices.