feat: quiz page question rework (#181)

- Replace Bootstrap accordion with flat card list for questions
- Add HTML5 drag-and-drop reordering with placeholder-between-cards UX
  and amber/green/red save status indicator next to the heading
- Add edit button per question opening a Bootstrap modal (bo--modal-form
  Stimulus controller with X-Modal-Request header pattern)
- Show read-only view button instead of edit for locked/finalized quizzes
- Add BankQuestion edit modal in question bank tab using same infrastructure
- Move modal action buttons into modal-footer via <template data-modal-footer>
- Fix IS_AUTHENTICATED_FULLY 403: replace ROLE_USER with IS_AUTHENTICATED
  on all backoffice controllers and in security.yaml access_control

templates/backoffice/quiz/_question_form_body.html.twig

@@ -0,0 +1,35 @@
+{% import 'backoffice/partials/answer_row.html.twig' as macros %}
+
+{{ form_start(form) }}
+{{ form_row(form.question) }}
+
+<div data-controller="bo--form-collection"
+     data-bo--form-collection-prototype-value="{{ macros.answer_row(form.answers.vars.prototype)|e('html_attr') }}">
+    {{ form_label(form.answers) }}
+    {{ form_errors(form.answers) }}
+    <div data-bo--form-collection-target="collection">
+        {% for answerForm in form.answers %}
+            {{ macros.answer_row(answerForm) }}
+        {% endfor %}
+    </div>
+    {% do form.answers.setRendered %}
+    <div class="d-flex gap-2 mb-3">
+        <button type="button" class="btn btn-sm btn-outline-primary"
+                data-action="bo--form-collection#addItem">{{ 'Add answer'|trans }}</button>
+        <button type="button" class="btn btn-sm btn-outline-secondary"
+                data-action="bo--form-collection#sortAlphabetically">{{ 'Sort A–Z'|trans }}</button>
+        <button type="button" class="btn btn-sm btn-outline-secondary"
+                data-action="bo--form-collection#randomize">{{ 'Randomize'|trans }}</button>
+    </div>
+</div>
+
+{% if isModal ?? false %}
+    {% do form.save.setRendered %}
+{% endif %}
+{{ form_end(form) }}
+{% if isModal ?? false %}
+<template data-modal-footer>
+    <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">{{ 'Cancel'|trans }}</button>
+    <button type="submit" form="{{ form.vars.id }}" class="btn btn-primary">{{ 'Save'|trans }}</button>
+</template>
+{% endif %}