feat(services): multi-domain routing, split-horizon and OIDC hardening

Bundle of cross-role changes for the gymb services deployment:

- Traefik routers: OR-combine opnform/homarr/bookstack Host rules with new
  *_extra_domains (internal *.int.* FQDNs for a DMZ reverseproxy), and emit
  tls.certresolver only when traefik_cert_mode == acme (drawio, homarr,
  opnform, send).
- Split-horizon: bookstack_extra_hosts / opnform_extra_hosts add container
  /etc/hosts overrides so containers reach the IdP public FQDN over the LAN.
- bookstack: assert the OIDC issuer resolves concretely (reject "//v2.0"),
  allowing non-Entra IdPs that override bookstack_oidc_issuer.
- homarr: derive the bcrypt salt from the password digest so the admin hash
  is idempotent — no spurious template changes / container restarts.
- opnform: PATCH an existing OIDC connection instead of skipping (applies
  corrected inventory on re-run); add OIDC_FORCE_LOGIN (enabled only after
  bootstrap) and an optional direct-SSO ingress entrypoint.

Docs: READMEs and meta/argument_specs.yml updated for all new variables.

roles/homarr/tasks/main.yml

@@ -112,19 +112,17 @@
 # =====================================================================
 
 - name: Generate bcrypt hash for admin password
-  ansible.builtin.shell:
-    cmd: python3 -c "import bcrypt, sys; print(bcrypt.hashpw(sys.stdin.read().encode(), bcrypt.gensalt(rounds=10)).decode())"
-    stdin: "{{ homarr_admin_password }}"
-    stdin_add_newline: false
-  delegate_to: localhost
-  become: false
-  register: bcrypt_result
-  changed_when: false
-  no_log: true
-
-- name: Set bcrypt hash fact
   ansible.builtin.set_fact:
-    homarr_bcrypt_hash: "{{ bcrypt_result.stdout }}"
+    # Deterministic salt derived from the password's SHA-256 digest so the
+    # hash stays stable across runs (idempotent — no spurious template
+    # changes / container restarts when the password is unchanged). The
+    # bcrypt salt alphabet is [./A-Za-z0-9]; the digest's hex chars are
+    # a strict subset, so we just take the first 22.
+    homarr_bcrypt_hash: >-
+      {{ homarr_admin_password
+         | password_hash('bcrypt', rounds=10,
+                         salt=(homarr_admin_password
+                               | hash('sha256'))[:22]) }}
   no_log: true
 
 # =====================================================================
@@ -161,4 +159,4 @@
   register: seed_result
   changed_when: seed_result.rc == 0
   when: admin_exists.stdout == ""
-  notify: restart homarr
+  notify: restart homarr