Desktop Companion links remote llama.cpp server

The networking part matters more than the app choice: if the server stays bound to `127.0.0.1`, nothing else on the LAN can reach it.

• –llama.cpp's server defaults to `127.0.0.1:8080`; for remote access it needs to listen on `0.0.0.0` or the machine's LAN interface.
• –OpenAI-style clients usually target a `/v1` base URL, with actual requests landing on endpoints like `/v1/chat/completions`.
• –Desktop Companion's LM Studio support is useful here because it can treat the remote box like a local model host once the endpoint is reachable.
• –This setup is a clean way to keep inference off the gaming rig without changing the user-facing app on PC 3.
• –If you want a more polished remote workflow later, LM Studio's LM Link is a better fit than manually punching holes in the network.