refactor(bootstrap,configuration,environment): add defaults/main.yml and extract hardcoded values

roles/bootstrap/tasks/_normalize.yml

@@ -9,16 +9,3 @@
       Unsupported OS '{{ os | default("undefined") }}' for bootstrap.
       Supported: {{ bootstrap_os_task_map | dict2items | map(attribute='key') | join(', ') }}
     quiet: true
-  vars:
-    bootstrap_os_task_map:
-      almalinux: _dnf_family.yml
-      alpine: alpine.yml
-      archlinux: archlinux.yml
-      debian: debian.yml
-      fedora: _dnf_family.yml
-      opensuse: opensuse.yml
-      rocky: _dnf_family.yml
-      rhel: rhel.yml
-      ubuntu: ubuntu.yml
-      ubuntu-lts: ubuntu.yml
-      void: void.yml