fix(semaphore/collections): use full ansible-galaxy path from Semaphore venv

ansible-galaxy is not on the system PATH on figment — Semaphore manages
its own venv under /opt/semaphore/apps/ansible/<ver>/venv/bin/.
Discover the binary dynamically rather than relying on PATH.

ansible/roles/semaphore/tasks/collections.yml

@@ -17,10 +17,17 @@
     group: root
     mode: "0755"
 
+- name: Find ansible-galaxy binary on host
+  ansible.builtin.shell:
+    cmd: "find /opt/semaphore/apps/ansible -name ansible-galaxy -type f | sort -V | tail -1"
+  register: ansible_galaxy_bin
+  changed_when: false
+  failed_when: ansible_galaxy_bin.stdout == ""
+
 - name: Install Ansible collections into host collections directory
   ansible.builtin.command:
     cmd: >
-      ansible-galaxy collection install
+      {{ ansible_galaxy_bin.stdout }} collection install
       {{ item.name }}{% if item.version is defined %}:{{ item.version }}{% endif %}
       -p {{ semaphore_collections_dir }}
       --force