fix(ansible): use set_fact to override slm_colocated_frontend — include_vars beats task vars

include_vars has Ansible precedence 18 while task-level vars: has 17.
Loading slm_manager/defaults/main.yml (which has slm_colocated_frontend: false)
via include_vars was silently overriding vars: slm_colocated_frontend: true
on the template task, so the template always rendered in non-co-located mode.

Replace vars: on the template task with an explicit set_fact (precedence 19)
that runs after include_vars, ensuring the template sees true.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: mrveiss

autobot-slm-backend/ansible/playbooks/provision-fleet-roles.yml

@@ -349,14 +349,20 @@
       when: _is_slm_frontend_colocated | bool
       tags: ['frontend', 'slm-nginx', 'provision']
 
+    # include_vars (precedence 18) would override task vars (17) so use
+    # set_fact (precedence 19) to win over the defaults' false value.
+    - name: "SLM | Override slm_colocated_frontend=true for co-located re-render"
+      ansible.builtin.set_fact:
+        slm_colocated_frontend: true
+      when: _is_slm_frontend_colocated | bool
+      tags: ['frontend', 'slm-nginx', 'provision']
+
     - name: "SLM | Re-render SLM nginx config for co-located mode (#3012)"
       ansible.builtin.template:
         src: "{{ playbook_dir }}/../roles/slm_manager/templates/autobot-slm.conf.j2"
         dest: "/etc/nginx/sites-available/{{ slm_nginx_config | default('autobot-slm') }}"
         mode: "0644"
         backup: true
-      vars:
-        slm_colocated_frontend: true
       when: _is_slm_frontend_colocated | bool
       register: _slm_nginx_rerendered
       tags: ['frontend', 'slm-nginx', 'provision']