fix: resolve review round 2, E2E failures, and mypy error

Review blocker A — form error swap and false success:
- Change HTMX contract so forms target their own container (outerHTML)
  instead of appending to #comments-list
- Use OOB swaps to append approved comments to the correct target
- Add success/error message display inside form templates
- Remove hx-on::after-request handlers (no longer needed)

Review blocker B — reply rendering shape:
- Create _reply.html partial with compact reply markup
- Approved replies via HTMX now use compact template + OOB swap
  into parent's .replies-container
- Reply form errors render inside reply form container

E2E test fixes:
- Update 4 failing tests to wait for inline HTMX messages instead
  of redirect-based URL assertions
- Add aria-label='Comment form errors' to form error display
- Rename test_reply_submission_redirects to
  test_reply_submission_shows_moderation_message

Mypy internal error workaround:
- Add mypy override for apps.comments.views (django-stubs triggers
  internal error on ORM annotate() chain with mypy 1.11.2)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

templates/comments/_comment_form.html

@@ -1,9 +1,19 @@
 {% load static %}
 <div id="comment-form-container" class="bg-brand-surfaceLight dark:bg-brand-surfaceDark border border-zinc-200 dark:border-zinc-800 p-6">
   <h3 class="font-display font-bold text-xl mb-6">Post a Comment</h3>
+  {% if success_message %}
+  <div class="mb-4 p-3 font-mono text-sm bg-brand-cyan/10 text-brand-cyan border border-brand-cyan/20">
+    {{ success_message }}
+  </div>
+  {% endif %}
+  {% if comment_form.errors %}
+  <div aria-label="Comment form errors" class="mb-4 p-3 font-mono text-sm bg-red-50 dark:bg-red-900/20 text-red-600 dark:text-red-400 border border-red-200 dark:border-red-800">
+    {% for error in comment_form.non_field_errors %}<p>{{ error }}</p>{% endfor %}
+    {% for field in comment_form %}{% for error in field.errors %}<p>{{ field.label }}: {{ error }}</p>{% endfor %}{% endfor %}
+  </div>
+  {% endif %}
   <form method="post" action="{% url 'comment_post' %}" data-comment-form class="space-y-4"
-    hx-post="{% url 'comment_post' %}" hx-target="#comments-list" hx-swap="beforeend"
-    hx-on::after-request="if(event.detail.successful) { this.reset(); document.getElementById('comment-success')?.remove(); this.insertAdjacentHTML('beforebegin', '<div id=&quot;comment-success&quot; class=&quot;mb-4 p-3 font-mono text-sm bg-brand-cyan/10 text-brand-cyan border border-brand-cyan/20&quot;>Comment posted!</div>'); }">
+    hx-post="{% url 'comment_post' %}" hx-target="#comment-form-container" hx-swap="outerHTML">
     {% csrf_token %}
     <input type="hidden" name="article_id" value="{{ page.id }}" />
     <div class="grid grid-cols-1 md:grid-cols-2 gap-4">