What is your question?

On modrinth "Supported environments" is set to client only. However, "Curious Lanterns" mod requires it on server, so I put it there manually.

So, for me it looks like "server" should be added to "Supported environments". In this case, if you export modpack using PrismLauncher for example, it will correctly generate modrinth.index.json so you can use import it to server without any additional tinkering.