Refactor role naming for TLS and proxy stack

- Renamed role `srv-tls-core` → `sys-svc-certs`
- Renamed role `srv-https-stack` → `sys-stk-front-pure`
- Renamed role `sys-stk-front` → `sys-stk-front-proxy`
- Updated all includes, READMEs, meta, and dependent roles accordingly

This improves clarity and consistency of naming conventions for certificate management and proxy orchestration.

See: https://chatgpt.com/share/68b19f2c-22b0-800f-ba9b-3f2c8fd427b0

roles/sys-stk-front-pure/tasks/main.yml

@@ -0,0 +1,10 @@
+- block:
+  - name: Include dependencies
+    include_role:
+      name: '{{ item }}'
+    loop:
+    - srv-core
+    - sys-svc-cln-domains
+    - srv-letsencrypt
+  - include_tasks: utils/run_once.yml
+  when: run_once_sys_stk_front_pure is not defined