testing and docker replacements (#3968)

This PR restructures testing scripts and Docker configurations to use centralized compose files, introduces new Docker Compose variants with integrated frontend services, and updates related CI workflows.

Migrate test scripts to reference testing/compose files and streamline test flows with forced rebuilds and direct curl checks.
Add ultra-lite, security, and security-with-login compose files under testing/compose, each defining both backend and frontend services.
Rename and adjust frontend imports and update CI workflows to build and validate the frontend separately.

docker/compose/docker-compose.monolith.yml

@@ -1,40 +0,0 @@
-services:
-  stirling-pdf-monolith:
-    build:
-      context: ../..
-      dockerfile: docker/monolith/Dockerfile
-    container_name: stirling-pdf-monolith
-    restart: on-failure:5
-    deploy:
-      resources:
-        limits:
-          memory: 4G
-    healthcheck:
-      test: ["CMD-SHELL", "curl -f http://localhost:80/ && curl -f http://localhost:8080/api/v1/info/status | grep -q 'UP'"]
-      interval: 10s
-      timeout: 15s
-      retries: 16
-    ports:
-      - "3000:80"   # Frontend access
-      - "8080:8080" # Direct backend access (for debugging)
-    volumes:
-      - ../../stirling/latest/data:/usr/share/tessdata:rw
-      - ../../stirling/latest/config:/configs:rw
-      - ../../stirling/latest/logs:/logs:rw
-    environment:
-      DISABLE_ADDITIONAL_FEATURES: "true"
-      SECURITY_ENABLELOGIN: "false"
-      LANGS: "en_GB,en_US,ar_AR,de_DE,fr_FR,es_ES,zh_CN,zh_TW,ca_CA,it_IT,sv_SE,pl_PL,ro_RO,ko_KR,pt_BR,ru_RU,el_GR,hi_IN,hu_HU,tr_TR,id_ID"
-      SYSTEM_DEFAULTLOCALE: en-US
-      UI_APPNAME: Stirling-PDF
-      UI_HOMEDESCRIPTION: Single container Stirling-PDF
-      UI_APPNAMENAVBAR: Stirling-PDF Monolith
-      SYSTEM_MAXFILESIZE: "100"
-      METRICS_ENABLED: "true"
-      SYSTEM_GOOGLEVISIBILITY: "true"
-      SHOW_SURVEY: "true"
-
-volumes:
-  stirling-data:
-  stirling-config:
-  stirling-logs: