#2 - Simplify NodeSource setup, clean up Dockerfile

Streamlined Node.js installation using NodeSource setup script, added cache cleanup to reduce image size, and updated verification step.

Dockerfile

@@ -35,15 +35,11 @@ RUN apt-get update && \
 # -------------------------------------------------------------------
 # Install Node.js from the official NodeSource repository (no NVM)
 # -------------------------------------------------------------------
-RUN curl -fsSL https://deb.nodesource.com/gpgkey/nodesource.gpg.key \
+RUN curl -fsSL "https://deb.nodesource.com/setup_${NODE_MAJOR}.x" | bash - && \
-       | gpg --dearmor -o /usr/share/keyrings/nodesource.gpg && \
+    apt-get update && apt-get install -y nodejs npm && \
-    echo "deb [signed-by=/usr/share/keyrings/nodesource.gpg] \
+    # Clean up apt cache to reduce image size
-         https://deb.nodesource.com/node_${ARG_NODE_MAJOR}.x nodistro main" \
+    rm -rf /var/lib/apt/lists/*
-         > /etc/apt/sources.list.d/nodesource.list && \
+
-    apt-get update && \
-    apt-get install -y nodejs && \
-    # optional: verify installation
-    node --version && npm --version \
 
 # -------------------------------------------------------------------
 # Global npm tools
@@ -75,3 +71,7 @@ RUN curl -sL ${GITIGNORE_URL} -o /home/coder/.gitignore && \
 
 # Install Firebase CLI
 RUN curl -sL firebase.tools | bash
+
+
+# optional: verify installation \
+RUN echo "node version $(node --version) | npm version $(npm --version)"