Are you trying to get the TLS cert for domains you own, or are you getting certs for all other domains? For the former, the Caddy ACME DNS plugin should work.

Are you trying to get the TLS cert for domains you own, or are you getting certs for all other domains? For the former, the Caddy ACME DNS plugin should work. For the latter, I think mitmproxy or similar would handle the on demand TLS cert creation. There's commercial intercept proxies as well, but I have no experience with them.