docs: add playbook documentation for NVIDIA device plugin and vLLM setup

playbooks/setup_nvidia_device_plugin.yml

@@ -0,0 +1,6 @@
+---
+- name: NVIDIA Device Plugin | Install via Helm with GPU Feature Discovery
+  hosts: manager_nodes
+  become: false
+  roles:
+    - nvidia_device_plugin

playbooks/setup_vllm.yml

@@ -0,0 +1,6 @@
+---
+- name: vLLM | Install vLLM via Helm
+  hosts: manager_nodes
+  become: false
+  roles:
+    - vllm