Allow configuring the admin URL path of the Pi-hole instance

Allow configuring the admin URL path of the Pi-hole instance: a task in MiMo-V2.6-RL-oss: Agentic RL Environments (MiMo RL release). I run my Pi-hole behind a reverse proxy and the admin UI isn't reachable at the default /admin/ path — I've moved it to a different path prefix (e.g. /pihole/) so it…