refactor: hoist OS-specific package names to role defaults

- nfs_server: nfs_package_name (nfs-utils / nfs-kernel-server)
- wireguard: wireguard_package_name (wireguard-tools / wireguard)
- tooling:   tooling_dig_package, tooling_netcat_package

Also fix tooling role structure: move tooling.yml to tasks/main.yml so
the role is actually invokable via 'role: tooling' (defaults/main.yml
is auto-loaded), and collapse the 10 individual package tasks into a
single list-based install.

roles/tooling/defaults/main.yml

@@ -0,0 +1,6 @@
+---
+# OS-dependent package names
+tooling_dig_package: >-
+  {{ (ansible_facts['os_family'] == 'Archlinux') | ternary('bind', 'dnsutils') }}
+tooling_netcat_package: >-
+  {{ (ansible_facts['os_family'] == 'Archlinux') | ternary('openbsd-netcat', 'netcat-openbsd') }}

roles/tooling/tasks/main.yml

@@ -0,0 +1,15 @@
+---
+- name: Install command-line tooling
+  ansible.builtin.package:
+    name:
+      - usbutils
+      - htop
+      - bottom
+      - wget
+      - ethtool
+      - iperf3
+      - vim
+      - nano
+      - "{{ tooling_dig_package }}"
+      - "{{ tooling_netcat_package }}"
+    state: present

roles/tooling/tooling.yml

@@ -1,60 +0,0 @@
----
-- name: Install usbutils
-  package:
-    name: usbutils
-    state: present
-  changed_when: false
-
-- name: Install htop
-  package:
-    name: htop
-    state: present
-  changed_when: false
-
-- name: Install bottom
-  package:
-    name: bottom
-    state: present
-  changed_when: false
-
-- name: Install wget
-  package:
-    name: wget
-    state: present
-  changed_when: false
-
-- name: Install dig utility
-  package:
-    name: "{{ (ansible_facts['os_family'] == 'Archlinux') | ternary('bind', 'dnsutils') }}"
-    state: present
-  changed_when: false
-
-- name: Install ethtool
-  package:
-    name: ethtool
-    state: present
-  changed_when: false
-
-- name: Install iperf3
-  package:
-    name: iperf3
-    state: present
-  changed_when: false
-
-- name: Install vim
-  package:
-    name: vim
-    state: present
-  changed_when: false
-
-- name: Install nano
-  package:
-    name: nano
-    state: present
-  changed_when: false
-
-- name: Install netcat
-  package:
-    name: "{{ (ansible_facts['os_family'] == 'Archlinux') | ternary('openbsd-netcat', 'netcat-openbsd') }}"
-    state: present
-  changed_when: false