fix: nav/footer wireframe, honeypot CSP, explore topics, comment E2E coverage

- Replace nav inline newsletter form with Subscribe CTA link per wireframe
- Remove newsletter form from footer; add Connect section with social/RSS links
- Fix honeypot inputs using hidden attribute (inline style blocked by CSP)
- Add available_tags to HomePage.get_context for Explore Topics section
- Add data-comment-form attribute to main comment form for reliable locating
- Seed approved comment in E2E content for reply flow testing
- Expand test_comments.py: moderation message, not-immediately-visible,
  missing fields, reply form visible, reply submission
- Make COMMENT_RATE_LIMIT_PER_MINUTE configurable; set 100 in dev to prevent
  E2E test exhaustion; update rate limit unit test with override_settings
- Update newsletter/home E2E tests to reflect nav form removal
- Update unit test to assert no nav/footer newsletter forms

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

templates/components/nav.html

@@ -14,15 +14,7 @@
       <a href="/" class="hover:text-brand-cyan transition-colors">Home</a>
       <a href="/articles/" class="hover:text-brand-cyan transition-colors">Articles</a>
       <a href="/about/" class="hover:text-brand-pink transition-colors">About</a>
-      <form method="post" action="/newsletter/subscribe/" data-newsletter-form class="flex items-center gap-2" id="nav-newsletter">
-        {% csrf_token %}
-        <input type="hidden" name="source" value="nav" />
-        <input type="email" name="email" required placeholder="dev@example.com"
-          class="bg-transparent border border-zinc-300 dark:border-zinc-700 px-3 py-2 text-brand-dark dark:text-brand-light font-mono text-sm focus:outline-none focus:border-brand-pink transition-colors w-44" />
-        <input type="text" name="honeypot" style="display:none" />
-        <button type="submit" class="px-5 py-2.5 bg-brand-dark dark:bg-brand-light text-brand-light dark:text-brand-dark font-display font-bold hover:-translate-y-1 hover:shadow-solid-dark dark:hover:shadow-solid-light transition-all border border-transparent dark:border-zinc-700 whitespace-nowrap">Subscribe</button>
-        <p data-newsletter-message aria-live="polite" class="font-mono text-xs text-brand-cyan min-h-[1rem]"></p>
-      </form>
+      <a href="#newsletter" class="px-5 py-2.5 bg-brand-dark dark:bg-brand-light text-brand-light dark:text-brand-dark font-display font-bold hover:-translate-y-1 hover:shadow-solid-dark dark:hover:shadow-solid-light transition-all border border-transparent dark:border-zinc-700">Subscribe</a>
     </div>
 
     <!-- Theme Toggle + Hamburger -->
@@ -49,7 +41,7 @@
       <input type="hidden" name="source" value="nav-mobile" />
       <input type="email" name="email" required placeholder="dev@example.com"
         class="w-full bg-transparent border border-zinc-300 dark:border-zinc-700 px-3 py-2 text-brand-dark dark:text-brand-light font-mono text-sm focus:outline-none focus:border-brand-pink transition-colors" />
-      <input type="text" name="honeypot" style="display:none" />
+      <input type="text" name="honeypot" hidden />
       <button type="submit" class="w-full px-4 py-2.5 bg-brand-dark dark:bg-brand-light text-brand-light dark:text-brand-dark font-display font-bold transition-colors">Subscribe</button>
       <p data-newsletter-message aria-live="polite" class="font-mono text-xs text-brand-cyan min-h-[1rem]"></p>
     </form>