fix(docker): set HOME environment variable explicitly in Dockerfile

The HOME environment variable was defaulting to /root when the container started, causing cache directories to be incorrectly set up under /root/.cache/zebra instead of /home/zebra/.cache/zebra. This explicit setting ensures the HOME environment variable is correctly set to the zebra user's home directory.

Author: gustavovalverde

docker/Dockerfile

@@ -72,6 +72,7 @@ ENV GID=${GID}
 ARG USER
 ENV USER=${USER}
 ARG HOME
+ENV HOME=${HOME}
 
 RUN addgroup --quiet --gid ${GID} ${USER} && \
     adduser --quiet --gid ${GID} --uid ${UID} --home ${HOME} ${USER} --disabled-password --gecos ""
@@ -191,6 +192,7 @@ ENV GID=${GID}
 ARG USER
 ENV USER=${USER}
 ARG HOME
+ENV HOME=${HOME}
 
 RUN addgroup --quiet --gid ${GID} ${USER} && \
     adduser --quiet --gid ${GID} --uid ${UID} --home ${HOME} ${USER} --disabled-password --gecos ""