fix: make user_setup and download tasks idempotent

The "Enable lingering" task always reported changed=true, and the
"Download gitea_runner binary" task used force=true which always
re-downloads. Both caused molecule idempotence tests to fail.

- Check /var/lib/systemd/linger/<user> before enabling lingering
- Set force=false on get_url so binary is only downloaded if missing

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

ansible/roles/gitea-runner/tasks/download_gitea_runner.yml

@@ -40,7 +40,7 @@
     url: "{{ gitea_runner_url }}"
     dest: "{{ gitea_runner_binary_path }}"
     mode: "0755"
-    force: true
+    force: false
   register: gitea_runner_download
   notify: Restart gitea-runner
   retries: 3

ansible/roles/gitea-runner/tasks/user_setup.yml

@@ -12,9 +12,14 @@
   ansible.builtin.set_fact:
     gitea_runner_uid: "{{ runner_user.uid }}"
 
+- name: Check if lingering is already enabled
+  ansible.builtin.stat:
+    path: "/var/lib/systemd/linger/{{ gitea_runner_service_user }}"
+  register: linger_stat
+
 - name: Enable lingering for runner user
   ansible.builtin.command: loginctl enable-linger {{ gitea_runner_service_user }}
-  changed_when: true
+  changed_when: not linger_stat.stat.exists
 
 - name: Ensure subuid entry for runner user
   ansible.builtin.lineinfile: