fix: resolve critical issues in x-clean-vendordirs, x-foreach, x-ip

x-clean-vendordirs: remove broken msgr dependency (not sourced),
add set -euo pipefail. x-foreach: replace eval on command args with
direct "$@" execution, add usage guard. x-ip: add set -euo pipefail,
curl dependency check, and silent-fail flag.

local/bin/x-ip

@@ -1,4 +1,14 @@
 #!/usr/bin/env bash
+#
+# Display external IP address.
+#
 # Source: https://github.com/thirtythreeforty/dotfiles/blob/master/bin/extip
 
-curl icanhazip.com "${@}"
+set -euo pipefail
+
+if ! command -v curl &> /dev/null; then
+  echo "Error: curl is required" >&2
+  exit 1
+fi
+
+curl -sf icanhazip.com