Revert to system-wide code-server installation

- Move code-server installation back to Dockerfile
- Remove per-user installation from entrypoint.sh
- System-wide installation is more efficient for single-user containers

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

entrypoint.sh

@@ -29,8 +29,6 @@ chmod 700 /home/$XWINDOW_USER
 mkdir -p /mnt
 chown $XWINDOW_USER:$XWINDOW_USER /mnt
 
-
-
 # add sudo group
 usermod -aG sudo $XWINDOW_USER
 
@@ -57,11 +55,6 @@ set -e
 # clean chromium config for fresh start
 su - $XWINDOW_USER -c "rm -rf ~/.config/chromium/"   
 
-# install code-server for user if not exists
-echo "Installing code-server for user $XWINDOW_USER..."
-su - $XWINDOW_USER -c "curl -fsSL https://code-server.dev/install.sh | sh -s -- --method standalone"
-
-
 # start code-server in background
 su - $XWINDOW_USER -c "code-server --bind-addr 0.0.0.0:30145 --auth password /mnt" &