add zig installation via tarball

tasks/pkgs/vault.yml

@@ -2,7 +2,8 @@
 - name: ensure hashicorp repo is active
   ansible.builtin.include_tasks:
     file: "pkgs/hashicorp_repo.yml"
+  when: pkgconfig_hashicorp not defined
 
 - name: append to pkgs
-  set_fact:
-    tappkgs: "{{ tappkgs + [ pkgconfig.hashicorp.vault[ansible_system] ] }}"
+  ansible.builtin.set_fact:
+    tappkgs: "{{ tappkgs + [ pkgconfig_hashicorp.vault[ansible_system] ] }}"