feat: added the terraform zsh completion script

Author: kurone-kito

.zsh.d/z-terraform

@@ -0,0 +1,12 @@
+#!/bin/sh
+# -*- mode: sh -*-
+# vim: set ft=sh :
+
+# =========================================================
+# ! WARN: DO NOT REMOVE THE “z” PREFIX!
+#
+# Added the “z” prefix to the filename because
+# the script has to run it after Homebrew's path resolution.
+
+autoload -U +X bashcompinit && bashcompinit
+complete -o nospace -C /opt/homebrew/bin/terraform terraform