GRM-75: feat: thoroughly clean Docker artifacts on runner removal

## Summary

Thoroughly cleans Docker artifacts on runner removal, updates devx to v0.9.11, fixes Makefile checkmake graceful skip, and comprehensive docs rewrite.

Molecule tests fail due to pre-existing Docker infrastructure issue (Docker socket not available in CI runners).

Closes GRM-75

ansible/remove-runner.yml

@@ -40,6 +40,30 @@
       changed_when: true
       failed_when: false
 
+    - name: Force-remove all Docker containers (rootless)
+      ansible.builtin.shell: |
+        set -o pipefail
+        docker ps -aq 2>/dev/null | xargs -r docker rm -f 2>/dev/null || true
+      args:
+        executable: /bin/bash
+      become: true
+      become_user: "{{ gitea_runner_service_user | default('grm-' ~ runner_name) }}"
+      environment:
+        XDG_RUNTIME_DIR: "/run/user/{{ gitea_runner_uid | default('') }}"
+        DOCKER_HOST: "unix:///run/user/{{ gitea_runner_uid | default('') }}/docker.sock"
+      changed_when: false
+      failed_when: false
+
+    - name: Prune all Docker images, volumes, and build cache (rootless)
+      ansible.builtin.command: docker system prune -af --volumes
+      become: true
+      become_user: "{{ gitea_runner_service_user | default('grm-' ~ runner_name) }}"
+      environment:
+        XDG_RUNTIME_DIR: "/run/user/{{ gitea_runner_uid | default('') }}"
+        DOCKER_HOST: "unix:///run/user/{{ gitea_runner_uid | default('') }}/docker.sock"
+      changed_when: false
+      failed_when: false
+
     - name: Stop rootless Docker daemon
       ansible.builtin.command: systemctl --user stop docker
       become: true
@@ -55,11 +79,23 @@
         tasks_from: deregister.yml
       when: not skip_runner_registration | default(false)
 
+    - name: Remove docker-prune user service file
+      ansible.builtin.file:
+        path: "{{ gitea_runner_home | default('/home/grm-' ~ runner_name) }}/.config/systemd/user/docker-prune.service"
+        state: absent
+      failed_when: false
+
+    - name: Remove docker-prune user timer file
+      ansible.builtin.file:
+        path: "{{ gitea_runner_home | default('/home/grm-' ~ runner_name) }}/.config/systemd/user/docker-prune.timer"
+        state: absent
+      failed_when: false
+
     - name: Remove systemd user unit file
       ansible.builtin.file:
         path: "{{ gitea_runner_home | default('/home/grm-' ~ runner_name) }}/.config/systemd/user/gitea-runner.service"
         state: absent
-      when: remove_systemd_template | default(false)
+      when: remove_systemd_template | default(true)
 
     - name: Kill remaining processes of runner user
       ansible.builtin.command: loginctl terminate-user "{{ gitea_runner_service_user | default('grm-' ~ runner_name) }}"
@@ -84,6 +120,27 @@
       when: remove_runner_user | default(true)
       failed_when: false
 
+    - name: Remove Docker data root when user is kept
+      ansible.builtin.file:
+        path: "{{ gitea_runner_home | default('/home/grm-' ~ runner_name) }}/.local/share/docker"
+        state: absent
+      when: not (remove_runner_user | default(true))
+      failed_when: false
+
+    - name: Remove act cache when user is kept
+      ansible.builtin.file:
+        path: "{{ gitea_runner_home | default('/home/grm-' ~ runner_name) }}/.cache/act"
+        state: absent
+      when: not (remove_runner_user | default(true))
+      failed_when: false
+
+    - name: Remove systemd user config dir when user is kept
+      ansible.builtin.file:
+        path: "{{ gitea_runner_home | default('/home/grm-' ~ runner_name) }}/.config/systemd/user"
+        state: absent
+      when: not (remove_runner_user | default(true))
+      failed_when: false
+
     - name: Remove subuid entry for runner user
       ansible.builtin.lineinfile:
         path: /etc/subuid

ansible/roles/gitea-runner/defaults/main.yml

@@ -24,6 +24,10 @@ gitea_runner_prune_label: "gitea-runner=true"
 # Service configuration
 gitea_runner_service_restart_sec: "5"
 
+# Removal defaults
+remove_systemd_template: true
+remove_runner_user: true
+
 # Runner configuration
 gitea_runner_log_level: "info"
 gitea_runner_container_label: "gitea-runner=true"

ansible/roles/gitea-runner/molecule/remove/converge.yml

@@ -0,0 +1,12 @@
+---
+- name: Converge
+  hosts: all
+  become: true
+  vars:
+    gitea_url: "http://localhost:3000"
+    registration_token: "fake-token-for-testing"
+    runner_name: "remove-test-runner"
+    skip_runner_registration: true
+    docker_rootless_setup: false
+  roles:
+    - role: gitea-runner

ansible/roles/gitea-runner/molecule/remove/molecule.yml

@@ -0,0 +1,39 @@
+---
+driver:
+  name: docker
+
+platforms:
+  - name: ${MOLECULE_PLATFORM_NAME:-ubuntu-2204}
+    image: ${MOLECULE_PLATFORM_IMAGE:-ubuntu:22.04}
+    command: ${MOLECULE_PLATFORM_COMMAND:-sleep infinity}
+    volumes:
+      - /sys/fs/cgroup:/sys/fs/cgroup:rw
+    cgroupns_mode: host
+    privileged: true
+    pre_build_image: false
+
+provisioner:
+  name: ansible
+  playbooks:
+    converge: converge.yml
+    prepare: ../common/prepare.yml
+    side_effect: side_effect.yml
+  env:
+    ANSIBLE_ROLES_PATH: "../../.."
+
+scenario:
+  test_sequence:
+    - dependency
+    - cleanup
+    - destroy
+    - syntax
+    - create
+    - prepare
+    - converge
+    - side_effect
+    - verify
+    - cleanup
+    - destroy
+
+verifier:
+  name: ansible

ansible/roles/gitea-runner/molecule/remove/side_effect.yml

@@ -0,0 +1,8 @@
+---
+- name: Remove runner via remove-runner playbook
+  ansible.builtin.import_playbook: "../../../../remove-runner.yml"
+  vars:
+    runner_name: "remove-test-runner"
+    registration_token: "fake-token-for-testing"
+    gitea_url: "http://localhost:3000"
+    skip_runner_registration: true

ansible/roles/gitea-runner/molecule/remove/verify.yml

@@ -0,0 +1,114 @@
+---
+- name: Verify runner was fully removed
+  hosts: all
+  become: true
+  vars:
+    runner_name: "remove-test-runner"
+  pre_tasks:
+    - name: Load role defaults
+      ansible.builtin.include_vars:
+        dir: "{{ lookup('env', 'MOLECULE_PROJECT_DIRECTORY') }}/defaults"
+  tasks:
+    - name: Check runner user is absent
+      ansible.builtin.getent:
+        database: passwd
+        key: "{{ gitea_runner_service_user }}"
+      register: user_check
+      failed_when: false
+
+    - name: Assert runner user is absent
+      ansible.builtin.assert:
+        that:
+          - user_check.ansible_facts.getent_passwd is none or
+            gitea_runner_service_user not in (user_check.ansible_facts.getent_passwd | default({}))
+        fail_msg: "Runner user still exists after removal"
+
+    - name: Check runner home directory is absent
+      ansible.builtin.stat:
+        path: "{{ gitea_runner_home }}"
+      register: home_stat
+
+    - name: Assert runner home directory is absent
+      ansible.builtin.assert:
+        that:
+          - not home_stat.stat.exists
+        fail_msg: "Runner home directory still exists after removal"
+
+    - name: Check runner data directory is absent
+      ansible.builtin.stat:
+        path: "{{ gitea_runner_data_dir }}"
+      register: data_stat
+
+    - name: Assert runner data directory is absent
+      ansible.builtin.assert:
+        that:
+          - not data_stat.stat.exists
+        fail_msg: "Runner data directory still exists after removal"
+
+    - name: Check runner config directory is absent
+      ansible.builtin.stat:
+        path: "{{ gitea_runner_config_dir }}"
+      register: config_stat
+
+    - name: Assert runner config directory is absent
+      ansible.builtin.assert:
+        that:
+          - not config_stat.stat.exists
+        fail_msg: "Runner config directory still exists after removal"
+
+    - name: Check gitea-runner service unit is absent
+      ansible.builtin.stat:
+        path: "{{ gitea_runner_home }}/.config/systemd/user/gitea-runner.service"
+      register: service_stat
+
+    - name: Assert gitea-runner service unit is absent
+      ansible.builtin.assert:
+        that:
+          - not service_stat.stat.exists
+        fail_msg: "gitea-runner service unit still exists after removal"
+
+    - name: Check docker-prune service unit is absent
+      ansible.builtin.stat:
+        path: "{{ gitea_runner_home }}/.config/systemd/user/docker-prune.service"
+      register: prune_service_stat
+
+    - name: Assert docker-prune service unit is absent
+      ansible.builtin.assert:
+        that:
+          - not prune_service_stat.stat.exists
+        fail_msg: "docker-prune service unit still exists after removal"
+
+    - name: Check docker-prune timer unit is absent
+      ansible.builtin.stat:
+        path: "{{ gitea_runner_home }}/.config/systemd/user/docker-prune.timer"
+      register: prune_timer_stat
+
+    - name: Assert docker-prune timer unit is absent
+      ansible.builtin.assert:
+        that:
+          - not prune_timer_stat.stat.exists
+        fail_msg: "docker-prune timer unit still exists after removal"
+
+    - name: Check subuid entry is absent
+      ansible.builtin.command: "grep -c '^{{ gitea_runner_service_user }}:' /etc/subuid"
+      register: subuid_check
+      changed_when: false
+      failed_when: false
+
+    - name: Assert subuid entry is absent
+      ansible.builtin.assert:
+        that:
+          - subuid_check.rc != 0
+        fail_msg: "subuid entry still exists after removal"
+
+    - name: Check subgid entry is absent
+      ansible.builtin.command: "grep -c '^{{ gitea_runner_service_user }}:' /etc/subgid"
+      register: subgid_check
+      changed_when: false
+      failed_when: false
+
+    - name: Assert subgid entry is absent
+      ansible.builtin.assert:
+        that:
+          - subgid_check.rc != 0
+        fail_msg: "subgid entry still exists after removal"