Use a different method for allowing non-TLS redirect URIs

Use a different method for allowing non-TLS redirect URIs: a task in MiMo-V2.6-RL-oss: Agentic RL Environments (MiMo RL release). I think requiring an environment variable named DEBUG to allow non-TLS redirect URIs isn't the best method. At the very least, it should be named something that won't…