Rework all roles to include component_(docker|container)_image_registry_prefix* variables

This:

- brings consistency - no more mixing `_name_prefix` and `_registry_prefix`
- adds extensibility - a future patch will allow reconfiguring all registry prefixes for all roles in the playbook

We still have `_docker_` vs `_container_` inconsistencies.
These may be worked on later.

roles/custom/matrix-appservice-draupnir-for-all/defaults/main.yml

@@ -10,8 +10,10 @@ matrix_appservice_draupnir_for_all_version: "v2.1.0"
 matrix_appservice_draupnir_for_all_container_image_self_build: false
 matrix_appservice_draupnir_for_all_container_image_self_build_repo: "https://github.com/the-draupnir-project/Draupnir.git"
 
-matrix_appservice_draupnir_for_all_docker_image: "{{ matrix_appservice_draupnir_for_all_docker_image_name_prefix }}gnuxie/draupnir:{{ matrix_appservice_draupnir_for_all_version }}"
-matrix_appservice_draupnir_for_all_docker_image_name_prefix: "{{ 'localhost/' if matrix_appservice_draupnir_for_all_container_image_self_build else 'docker.io/' }}"
+matrix_appservice_draupnir_for_all_docker_image_registry_prefix: "{{ 'localhost/' if matrix_appservice_draupnir_for_all_container_image_self_build else matrix_appservice_draupnir_for_all_docker_image_registry_prefix_upstream }}"
+matrix_appservice_draupnir_for_all_docker_image_registry_prefix_upstream: "{{ matrix_appservice_draupnir_for_all_docker_image_registry_prefix_upstream_default }}"
+matrix_appservice_draupnir_for_all_docker_image_registry_prefix_upstream_default: "docker.io/"
+matrix_appservice_draupnir_for_all_docker_image: "{{ matrix_appservice_draupnir_for_all_docker_image_registry_prefix }}gnuxie/draupnir:{{ matrix_appservice_draupnir_for_all_version }}"
 matrix_appservice_draupnir_for_all_docker_image_force_pull: "{{ matrix_appservice_draupnir_for_all_docker_image.endswith(':latest') }}"
 
 matrix_appservice_draupnir_for_all_base_path: "{{ matrix_base_data_path }}/draupnir-for-all"

roles/custom/matrix-appservice-draupnir-for-all/tasks/validate_config.yml

@@ -7,3 +7,12 @@
     - "matrix_appservice_draupnir_for_all_master_control_room_alias"
     - "matrix_bot_draupnir_container_network"
   when: "vars[item] == '' or vars[item] is none"
+
+- name: (Deprecation) Catch and report renamed matrix-appservice-draupnir-for-all settings
+  ansible.builtin.fail:
+    msg: >-
+      Your configuration contains a variable, which now has a different name.
+      Please change your configuration to rename the variable (`{{ item.old }}` -> `{{ item.new }}`).
+  when: "item.old in vars"
+  with_items:
+    - {'old': 'matrix_appservice_draupnir_for_all_docker_image_name_prefix', 'new': 'matrix_appservice_draupnir_for_all_docker_image_registry_prefix'}