Add container-aware execution logic and CI stability fixes

- Introduce global IS_CONTAINER flag based on ansible_virtualization facts
- Skip systemd-based handlers and tasks when running inside containers
- Extend EXCLUDED_ROLES list in GitHub Actions test-deploy workflow
- Ensure docker.sock is mounted for all CI deploy stages
- Improve sys-svc-docker by suppressing service restarts inside containers
- Add meta: flush_handlers to properly trigger delayed docker restarts
- Update sys-service handlers with container guards
- Update sys-timer tasks to avoid systemctl inside CI containers
- Enhance drv-non-free role with Manjaro detection and mhwd fallback warning
- Skip swapfile generation in containers
- Minor service template fixes and cleanup in proxy.conf.j2

Details and discussion: https://chatgpt.com/share/6930a4ca-56f4-800f-9b3d-4791f040a03b

roles/drv-non-free/tasks/main.yml

@@ -1,2 +1,32 @@
-- name: Install nonfree drivers
-  ansible.builtin.shell: mhwd -a pci nonfree 0300
+- name: Gather OS facts (ensure we know distribution)
+  ansible.builtin.setup:
+  when: ansible_facts is not defined
+
+- name: Ensure mhwd is installed on Manjaro
+  community.general.pacman:
+    name: mhwd
+    state: present
+  become: true
+  when:
+    - ansible_facts['distribution'] is defined
+    - ansible_facts['distribution'] in ['ManjaroLinux', 'Manjaro']
+  register: mhwd_install
+
+- name: Detect mhwd command
+  ansible.builtin.stat:
+    path: /usr/bin/mhwd
+  register: mhwd_binary
+
+- name: Install nonfree drivers via mhwd (Manjaro only)
+  ansible.builtin.shell: mhwd -a pci nonfree 0300
+  become: true
+  when:
+    - mhwd_binary.stat.exists
+
+- name: Warn when mhwd is not available
+  ansible.builtin.debug:
+    msg: >
+      Skipping proprietary GPU driver installation: `mhwd` not found.
+      This role currently only supports Manjaro (mhwd); on other distros it does nothing.
+  when:
+    - not mhwd_binary.stat.exists