Add mcp-servers playbook and role submodule

Cluster-internal, read-only MCP servers (Gitea, Grafana, Nextcloud,
Discourse) for the LocalAI agent pool, acting as LDAP user localai.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

mcp-servers.yaml

@@ -0,0 +1,5 @@
+- name: Deploy cluster-internal MCP servers for the LocalAI agent pool
+  hosts: alpha-control-plane
+  become: true
+  roles:
+    - role: ericomeehan.mcp-servers