Fix health check URL to include HTTP relative path

- Include keycloak_quarkus_http_relative_path in health_url construction
- Use rstrip('/') to handle both default '/' and custom paths like '/auth'
- Replace hardcoded 'master' realm with keycloak_quarkus_master_realm variable
- Add keycloak_quarkus_validate_certs option for SSL certificate validation
- Update documentation in meta and README

Fixes #299

roles/keycloak_quarkus/tasks/start.yml

@@ -10,7 +10,7 @@
 - name: "Wait until service becomes active: {{ keycloak.service_name }}"
   ansible.builtin.uri:
     url: "{{ keycloak.health_url }}"
-    validate_certs: "{{ keycloak_quarkus_validate_certs | default(omit) }}"
+    validate_certs: "{{ keycloak_quarkus_validate_certs }}"
   register: keycloak_quarkus_status
   until: keycloak_quarkus_status.status == 200
   retries: 25