Switching over to using unix sockets for ICP

roles/postgresql/defaults/main.yml

@@ -13,10 +13,14 @@
 postgresql_service_enabled: true
 postgresql_service_state: "started"
 
-# Network Security (localhost only)
-postgresql_listen_addresses: "localhost"
+# Network Security (Unix socket only - no network listening)
+postgresql_listen_addresses: ""  # Empty string = no TCP/IP connections
 postgresql_port: 5432
 
+# Unix socket configuration
+postgresql_unix_socket_directories: "/run/postgresql"
+postgresql_unix_socket_permissions: 0777  # Allows container access
+
 # Authentication
 postgresql_auth_method: "scram-sha-256"