fix: remove linux-patch-api user from dpkg scripts, change ownership to root

- Remove user/group creation from preinst (service runs as root)
- Change directory ownership to root:root in preinst and postinst
- Remove user/group deletion from postrm
- Service runs as root, no dedicated user needed

debian/postrm

@@ -39,18 +39,6 @@ if [ "$1" = "purge" ]; then
         rm -rf /var/log/linux_patch_api
     fi
     
-    # Remove system user
-    if getent passwd linux-patch-api > /dev/null 2>&1; then
-        echo "Removing user linux-patch-api..."
-        userdel linux-patch-api 2>/dev/null || true
-    fi
-    
-    # Remove system group
-    if getent group linux-patch-api > /dev/null 2>&1; then
-        echo "Removing group linux-patch-api..."
-        groupdel linux-patch-api 2>/dev/null || true
-    fi
-    
     echo "linux-patch-api purged successfully"
 fi