Add my docker and docker_compose role

Do this in preparation for the keycloak deployment.

playbooks/roles/docker_compose/tasks/main.yaml

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+- name: make sure the `/ansible_docker_compose` directory exists
+  ansible.builtin.file:
+    path: /ansible_docker_compose
+    state: directory
+    mode: "0755"
+    owner: root
+    group: root
+  become: true
+
+- name: deploy the Compose file
+  ansible.builtin.copy:
+    content: "{{ docker_compose__compose_file_content }}"
+    dest: /ansible_docker_compose/compose.yaml
+    mode: "0644"
+    owner: root
+    group: root
+  become: true
+  notify: docker compose down
+
+- name: make sure the `/ansible_docker_compose/configs` directory exists
+  ansible.builtin.file:
+    path: /ansible_docker_compose/configs
+    state: directory
+    mode: "0755"
+    owner: root
+    group: root
+  become: true
+
+- name: set `docker_compose__config_files_to_exist` fact initially to an empty list
+  ansible.builtin.set_fact:
+    docker_compose__config_files_to_exist: [ ]
+
+- name: add names from `docker_compose__configuration_files` to `docker_compose__config_files_to_exist` fact
+  ansible.builtin.set_fact:
+    docker_compose__config_files_to_exist: "{{ docker_compose__config_files_to_exist + [ item.name ] }}"  # noqa: jinja[spacing]
+  loop: "{{ docker_compose__configuration_files }}"
+
+- name: find configuration files to remove
+  ansible.builtin.find:
+    paths: /ansible_docker_compose/configs/
+    recurse: false
+    excludes: "{{ docker_compose__config_files_to_exist }}"
+  register: docker_compose__config_files_to_remove
+
+- name: remove all configuration files, which should be removed
+  ansible.builtin.file:
+    path: "{{ item.path }}"
+    state: absent
+  become: true
+  loop: "{{ docker_compose__config_files_to_remove.files }}"
+  notify: docker compose down
+
+- name: make sure all given configuration files are deployed
+  ansible.builtin.copy:
+    content: "{{ item.content }}"
+    dest: "/ansible_docker_compose/configs/{{ item.name }}"
+    mode: "0644"
+    owner: root
+    group: root
+  become: true
+  loop: "{{ docker_compose__configuration_files }}"
+  notify: docker compose down
+
+- name: Flush handlers to make "docker compose down" handler run now
+  ansible.builtin.meta: flush_handlers
+
+- name: docker compose ps --format json before docker compose up
+  ansible.builtin.command:
+    cmd: /usr/bin/docker compose ps --format json
+    chdir: /ansible_docker_compose
+  become: true
+  changed_when: false
+  register: docker_compose__ps_json_before_up
+
+- name: docker compose up --detach --pull always
+  ansible.builtin.command:
+    cmd: /usr/bin/docker compose up --detach --pull always
+    chdir: /ansible_docker_compose
+  become: true
+  changed_when: false
+  # The changed for this task is tried to be determined by the "potentially
+  # report changed" task together with the "docker compose ps --format json
+  # [...]" tasks.
+
+- name: docker compose ps --format json after docker compose up
+  ansible.builtin.command:
+    cmd: /usr/bin/docker compose ps --format json
+    chdir: /ansible_docker_compose
+  become: true
+  changed_when: false
+  register: docker_compose__ps_json_after_up
+
+- name: potentially report changed
+  ansible.builtin.debug:
+    msg: "If this reports changed, then the docker compose containers changed."
+  changed_when: (docker_compose__ps_json_before_up.stdout | from_json | community.general.json_query('[].ID') | sort)
+                != (docker_compose__ps_json_after_up.stdout | from_json | community.general.json_query('[].ID') | sort)