update 25hz yaml

fix lint

update fastapi

add llm export script

update stream code

change flow config in cosyvoice.fromscratch.yaml

FIX: 修复下载解压完成LibriTTS数据时，生成.complete文件失败，这导致每次执行download_and_untar.sh时都要重新下载数据。

move use_spk_embedding to processor

use spk_embedding when sft

add constant lr scheduler

remove academic third party

add cosyvoice code