hmm stupid mac 
Delete your bolt.diy directory and start from scratch.
then try these 2 commands (first is logging in as root at all, clones and installs it again):
sudo su
npm install -g pnpm && git clone -b stable https://github.com/stackblitz-labs/bolt.diy && cd bolt.diy && pnpm install && pnpm run dev
If this also not helping maybe @wonderwhy.er can help out here, as I know he´s also on a mac 