fix(universal): preserve login shell PATH for coder user (#332)

Author: matifali

images/universal/README.md

@@ -4,4 +4,4 @@
 
 ## Description
 
-Microsoft's [Universal Dev Container Image](https://github.com/devcontainers/images/tree/main/src/universal) extended with a `coder` user.
+Microsoft's [Universal Dev Container Image](https://github.com/devcontainers/images/tree/main/src/universal) with the upstream `codespace` user renamed to `coder`. The image keeps the base shell environment while rewriting hardcoded home paths and preserving inherited `PATH` entries for Coder's injected tooling.

images/universal/ubuntu.Dockerfile

@@ -12,14 +12,22 @@ RUN rm -R /opt/conda && \
 # Install Chrome for AI Browser Testing
 RUN yes | npx playwright install chrome
 
-# Create `coder` user
-RUN userdel -r codespace && \
-    useradd coder \
-    --create-home \
-    --shell=/bin/bash \
-    --groups=docker \
-    --uid=1000 \
-    --user-group && \
-echo "coder ALL=(ALL) NOPASSWD:ALL" >>/etc/sudoers.d/nopasswd
+# Rename the upstream `codespace` user to `coder` so we preserve the
+# existing home directory and shell environment provided by the base image.
+RUN usermod -l coder codespace && \
+    groupmod -n coder codespace && \
+    usermod -d /home/coder -m coder && \
+    usermod -aG docker,sudo coder && \
+    sed -i \
+        -e 's#/home/codespace#/home/coder#g' \
+        -e 's#^export PATH=#export PATH=${PATH:+$PATH:}#' \
+        /etc/profile.d/00-restore-env.sh && \
+    sed -i \
+        -e 's#codespace#coder#g' \
+        -e 's#/home/codespace#/home/coder#g' \
+        /etc/sudoers.d/codespace && \
+    mv /etc/sudoers.d/codespace /etc/sudoers.d/coder && \
+    echo "coder ALL=(ALL) NOPASSWD:ALL" >/etc/sudoers.d/nopasswd && \
+    chmod 0440 /etc/sudoers.d/coder /etc/sudoers.d/nopasswd
 
 USER coder