fix: enhance user detection for non-login environments in setup script

scripts/setup.sh

@@ -35,9 +35,16 @@ if ! command -v whiptail > /dev/null 2>&1; then
   fi
 fi
 
-# Detect user
-REAL_USER=${SUDO_USER:-$(logname)}
-REAL_HOME=$(eval echo "~$REAL_USER")
+# Detect user (supports non-login environments like Docker)
+REAL_USER=${SUDO_USER:-$(logname 2>/dev/null || true)}
+if [ -z "$REAL_USER" ]; then
+  REAL_USER=root
+fi
+REAL_HOME=$(eval echo "~$REAL_USER" 2>/dev/null || true)
+if [ -z "$REAL_HOME" ]; then
+  REAL_HOME=/root
+fi
+
 echo "Target User: $REAL_USER ($REAL_HOME)"
 
 # 0.5 SCRUB & SANITIZE PHASE