devcontainer: fix rc files, move CARLA_HOST to json (#30047)

* Download rc files to batman home directory. Fix links

* Move CARLA_HOST to devcontainer.json

* Remove user root
old-commit-hash: 3cf58e55eb58f5e94552edfd9b52408c967c8ba7

.devcontainer/Dockerfile

@@ -3,8 +3,8 @@ FROM ghcr.io/commaai/openpilot-base:latest
 RUN apt update && apt install -y vim net-tools usbutils htop ripgrep tmux
 RUN pip install ipython jupyter jupyterlab
 
+USER batman
+
 RUN cd $HOME && \
     curl -O https://raw.githubusercontent.com/commaai/agnos-builder/master/userspace/home/.tmux.conf && \
-    curl -O https://github.com/commaai/agnos-builder/blob/master/userspace/home/.vimrc
-
-ENV CARLA_HOST="host.docker.internal"
+    curl -O https://raw.githubusercontent.com/commaai/agnos-builder/master/userspace/home/.vimrc

.devcontainer/devcontainer.json

@@ -11,6 +11,7 @@
     "DISPLAY": "${localEnv:DISPLAY}",
     "PYTHONPATH": "${containerWorkspaceFolder}",
     "TERM": "xterm-256color",
+    "CARLA_HOST": "host.docker.internal",
     "force_color_prompt": "1"
   },
   "runArgs": [