Refactor resource configuration:

- Introduce new resource_filter plugin (mandatory hard_default, auto entity_name fallback)
- Replace get_app_conf calls with resource_filter in resource.yml.j2
- Add WEBSERVER_CPUS_EFFECTIVE, WEBSERVER_WORKER_PROCESSES, WEBSERVER_WORKER_CONNECTIONS to 05_webserver.yml
- Update Nginx templates (sys-svc-webserver, web-app-magento, web-app-nextcloud) to use new vars
- Extend svc-prx-openresty config with cpus/mem limits
- Add unit tests for resource_filter

Details: https://chatgpt.com/share/68d3a493-9a5c-800f-8cd2-bd2e7a3e3fda

roles/svc-prx-openresty/config/main.yml

@@ -1,7 +1,10 @@
 docker:
   services:
     openresty:
-      name: "openresty"
+      name:             "openresty"
+      cpus:             0.5
+      mem_reservation:  1g
+      mem_limit:        2g
   volumes:
     www:    "/var/www/"
     nginx:  "/etc/nginx/"