Refactor: migrate cmp/* and srv/* roles into sys-stk/* and sys-svc/* namespaces

- Removed obsolete 'cmp' category, introduced 'stk' category (fa-bars-staggered icon).
- Renamed roles:
  * cmp-db-docker → sys-stk-back-stateful
  * cmp-docker-oauth2 → sys-stk-back-stateless
  * srv-domain-provision → sys-stk-front
  * cmp-db-docker-proxy → sys-stk-full-stateful
  * cmp-docker-proxy → sys-stk-full-stateless
  * cmp-rdbms → sys-svc-rdbms
- Updated all include_role references, vars, templates and README.md files.
- Adjusted run_once comments and variable paths accordingly.
- Updated all web-app roles to use new sys-stk/* and sys-svc/* roles.

Conversation: https://chatgpt.com/share/68b0ba66-09f8-800f-86fc-76c47009d431

roles/sys-stk-full-stateless/tasks/main.yml

@@ -0,0 +1,13 @@
+# run_once_sys_stk_full_stateless: deactivated
+
+# Load the proxy first, so that openresty handlers are flushed before the main docker compose
+- name: "For '{{ application_id }}': include role sys-stk-front"
+  include_role:
+    name: sys-stk-front
+  vars:
+    domain:   "{{ domains | get_domain(application_id) }}"
+    http_port:   "{{ ports.localhost.http[application_id] }}"
+
+- name: "For '{{ application_id }}': Load sys-stk-back-stateless"
+  include_role: 
+    name: sys-stk-back-stateless