Implement reserved username handling for users, LDAP and Keycloak

Add end-to-end support for reserved usernames and tighten CAPTCHA / Keycloak logic.

Changes:

- Makefile: rename EXTRA_USERS → RESERVED_USERNAMES and pass it as --reserved-usernames to the users defaults generator.

- cli/build/defaults/users.py: propagate  flag into generated users, add --reserved-usernames CLI option and mark listed accounts as reserved.

- Add reserved_users filter plugin with  and  helpers for Ansible templates and tasks.

- Add unit tests for reserved_users filters and the new reserved-usernames behaviour in the users defaults generator.

- group_vars/all/00_general.yml: harden RECAPTCHA_ENABLED / HCAPTCHA_ENABLED checks with default('') and explicit > 0 length checks.

- svc-db-openldap: introduce OPENLDAP_PROVISION_* flags, add OPENLDAP_PROVISION_RESERVED and OPERNLDAP_USERS to optionally exclude reserved users from provisioning.

- svc-db-openldap templates/tasks: switch role/group LDIF and user import loops to use OPERNLDAP_USERS instead of the full users dict.

- networks: assign dedicated subnet for web-app-roulette-wheel.

- web-app-keycloak vars: compute KEYCLOAK_RESERVED_USERNAMES_LIST and KEYCLOAK_RESERVED_USERNAMES_REGEX from users | reserved_usernames.

- web-app-keycloak user profile template: inject reserved-username regex into username validation pattern and improve error message, fix SSH public key attribute usage and add component name field.

- web-app-keycloak update/_update.yml: strip subComponents from component payloads before update and disable async/poll for easier debugging.

- web-app-keycloak tasks/main.yml: guard cleanup include with MODE_CLEANUP and keep reCAPTCHA update behind KEYCLOAK_RECAPTCHA_ENABLED.

- user/users defaults: mark system/service accounts (root, daemon, mail, admin, webmaster, etc.) as reserved so they cannot be chosen as login names.

- svc-prx-openresty vars: simplify OPENRESTY_CONTAINER lookup by dropping unused default parameter.

- sys-ctl-rpr-btrfs-balancer: simplify main.yml by removing the extra block wrapper.

- sys-daemon handlers: quote handler name for consistency.

Context: change set discussed and refined in ChatGPT on 2025-11-29 (Infinito.Nexus reserved usernames & Keycloak user profile flow). See conversation: https://chatgpt.com/share/692b21f5-5d98-800f-8e15-1ded49deddc9

roles/web-app-keycloak/tasks/main.yml

@@ -5,6 +5,7 @@
 
 - name: "Load cleanup routine for '{{ application_id }}'"
   include_tasks: 02_cleanup.yml
+  when: MODE_CLEANUP | bool
 
 - name: "Load init routine for '{{ application_id }}'"
   include_tasks: 03_init.yml
@@ -35,3 +36,4 @@
 - name: "Load reCAPTCHA Update routines for '{{ application_id }}'"
   include_tasks: update/06_recaptcha.yml
   when: KEYCLOAK_RECAPTCHA_ENABLED | bool
+

roles/web-app-keycloak/tasks/update/_update.yml

@@ -146,6 +146,19 @@
       }}
   no_log: "{{ MASK_CREDENTIALS_IN_LOGS | bool }}"
 
+- name: Drop unsupported fields for components (e.g. subComponents)
+  when: kc_object_kind == 'component'
+  set_fact:
+    desired_obj: >-
+      {{
+        desired_obj
+        | dict2items
+        | rejectattr('key', 'equalto', 'subComponents')
+        | list
+        | items2dict
+      }}
+  no_log: "{{ MASK_CREDENTIALS_IN_LOGS | bool }}"
+
 - name: Preserve immutable fields for client-scope
   when: kc_object_kind == 'client-scope'
   set_fact:
@@ -181,5 +194,5 @@
     {{ desired_obj | to_json }}
     JSON
     {%- endif %}
-  async: "{{ ASYNC_TIME if ASYNC_ENABLED | bool else omit }}"
-  poll:  "{{ ASYNC_POLL if ASYNC_ENABLED | bool else omit }}"
+  #async: "{{ ASYNC_TIME if ASYNC_ENABLED | bool else omit }}"
+  #poll:  "{{ ASYNC_POLL if ASYNC_ENABLED | bool else omit }}"