Add the memcached plugin (object caching)

composer.json

@@ -131,7 +131,8 @@
         "wpackagist-plugin/event-organiser": "3.12.1",
         "noblogs/ai-authenticate-rest-api-plugin": "0.0.3",
         "wpackagist-plugin/multisite-custom-css": "1.0",
-        "wpackagist-plugin/activitypub": "0.13.4"
+        "wpackagist-plugin/activitypub": "0.13.4",
+        "wpackagist-plugin/memcached": "4.0.0"
     },    
     "extra": {
         "wordpress-install-dir": "app",
@@ -198,7 +199,8 @@
             ],
             "app/wp-content": [
                 "package:stuttter/ludicrousdb:ludicrousdb/drop-ins/db.php,ludicrousdb/drop-ins/db-error.php",
-                "package:wpackagist-plugin/wp-super-cache:advanced-cache.php"
+                "package:wpackagist-plugin/wp-super-cache:advanced-cache.php",
+                "package:wpackagist-plugin/memcached:object-cache.php"
             ],
             "app": [
                 "package:noblogs/r2db:db-config.php,nginx-map/wp-nginx-map-json.php,nginx-map/wp-nginx-map.php"