feat(opnform)!: add admin and OIDC bootstrap, rename role to lowercase

Rename roles/OpnForm → roles/opnform so the role resolves as
  digitalboard.core.opnform (Ansible collection convention is
  lowercase). Update tests/test.yml reference accordingly.

  Add automated admin user creation via POST /api/register, gated on
  opnform_admin_email + opnform_admin_password. Idempotent through a
  prior login probe. Without these vars the manual setup page flow is
  preserved.

  Add automated OIDC IdentityConnection setup via the per-workspace
  /api/open/workspaces/{id}/oidc-connections endpoint, gated on
  opnform_oidc_enabled. Hard-coupled to the admin bootstrap (the API
  requires an authenticated admin token); validation block fails fast
  if OIDC is enabled without admin credentials. Supports both an
  explicit opnform_oidc_group_role_mappings list and a fallback
  opnform_oidc_admin_group convenience var.

  Convert opnform_oidc_scopes from space-separated string to YAML list
  to match OpnForm's API expectation. Rewrite README "First login" and
  "OIDC setup" sections to reflect that self-hosted OpnForm does not
  ship a pre-seeded admin and to document the new bootstrap paths.
  BREAKING CHANGE: opnform_oidc_scopes changed from space-separated
  string to YAML list. Inventories that override it must update from
  "openid profile email" to [openid, profile, email].

roles/OpnForm/handlers/main.yml

@@ -1,8 +0,0 @@
-#SPDX-License-Identifier: MIT-0
----
-# handlers file for opnform
-
-- name: restart opnform
-  community.docker.docker_compose_v2:
-    project_src: "{{ opnform_docker_compose_dir }}"
-    state: restarted