organizing for go pkg installs

tasks/pkgs/go.yml

@@ -1,5 +1,13 @@
 # vim: set filetype=yaml.ansible :
 ---
-- name: Append to pkgs
+- name: Install from archive
+  when:
+    - prefer_archive
   ansible.builtin.set_fact:
-    src_pkgs: "{{ src_pkgs + ['go'] }}"
+    archive_pkgs: "{{ archive_pkgs + ['go'] }}"
+
+- name: Append to pkgs
+  when:
+    - not prefer_archive
+  ansible.builtin.set_fact:
+    sys_pkgs: "{{ src_pkgs + ['go'] }}"