Summary of changes:
"Server Action", like "Effect", is a React-specific notion
that would be benefited from captailization to be distinguished
from its genertic meaning.
It seems like [Next doc](https://nextjs.org/docs/app/api-reference/functions/server-actions)
has also adopted such connventions and we should probably do the same.
Co-authored-by: xuan.huang <xuan.huang@bytedance.com>
