refactor!: switch hosts variables to a flat layout

collections/ansible_collections/nullified/infrastructure/roles/common/defaults/main.yml

@@ -1,20 +1,14 @@
 ---
-common:
-  apt:
-    source_components: ['contrib', 'non-free', 'non-free-firmware']
-    packages: []
-    deb822_format: false
-  git:
-    enable: false
-    username: ""
-    email: ""
-    force_sign: false
-    signing_key: ""
-  github_token: "{{ custom_github_token | default('') }}"
-  install_fonts: false
-  sysctl: {}
-  user_account: "{{ custom_base_user_account | default('root') }}"
-  configure_resolv_conf: false
-
-custom_common: {}
-recursive_combine: true
+common_apt_packages: []
+common_apt_source_components: ["contrib", "non-free", "non-free-firmware"]
+common_apt_use_deb822_format: false
+common_configure_resolve_conf: false
+common_git_email: ""
+common_git_enabled: false
+common_git_force_sign: false
+common_git_signing_key: ""
+common_git_username: ""
+common_github_token: "{{ custom_github_token | default('') }}"
+common_install_fonts: false
+common_sysctl_configuration: {}
+common_user_account: "{{ custom_base_user_account }}"