Use non-root user by default, bundled lldb adapter

.devcontainer/Dockerfile

@@ -5,12 +5,17 @@
 
 FROM rust:1
 
+# Or your actual UID, GID on Linux if not the default 1000
+ARG USERNAME=vscode
+ARG USER_UID=1000
+ARG USER_GID=$USER_UID
+
 # Avoid warnings by switching to noninteractive
 ENV DEBIAN_FRONTEND=noninteractive
 
 # Configure apt and install packages
 RUN apt-get update \
-    && apt-get -y install --no-install-recommends apt-utils 2>&1 \
+    && apt-get -y install --no-install-recommends apt-utils dialog 2>&1 \
     #
     # Verify git, needed tools installed
     && apt-get -y install git procps lsb-release \
@@ -22,10 +27,18 @@ RUN apt-get update \
     && rustup update \
     && rustup component add rls rust-analysis rust-src \
     #
+    # Create a non-root user to use if preferred - see https://aka.ms/vscode-remote/containers/non-root-user.
+    && groupadd --gid $USER_GID $USERNAME \
+    && useradd -s /bin/bash --uid $USER_UID --gid $USER_GID -m $USERNAME \
+    # [Optional] Add sudo support for non-root user
+    && apt-get install -y sudo \
+    && echo $USERNAME ALL=\(root\) NOPASSWD:ALL > /etc/sudoers.d/$USERNAME \
+    && chmod 0440 /etc/sudoers.d/$USERNAME \
+    #
     # Clean up
     && apt-get autoremove -y \
     && apt-get clean -y \
     && rm -rf /var/lib/apt/lists/*
 
 # Switch back to dialog for any ad-hoc use of apt-get
-ENV DEBIAN_FRONTEND=dialog
+ENV DEBIAN_FRONTEND=