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>

apps/blog/tests/test_views.py

@@ -69,8 +69,12 @@ def test_newsletter_forms_render_in_nav_and_footer(client, home_page):
     resp = client.get("/")
     html = resp.content.decode()
     assert resp.status_code == 200
-    assert 'name="source" value="nav"' in html
-    assert 'name="source" value="footer"' in html
+    # Nav has a Subscribe CTA link (no inline form — wireframe spec)
+    assert 'href="#newsletter"' in html
+    # Footer has Connect section with social/RSS links (no newsletter form)
+    assert "Connect" in html
+    assert 'name="source" value="nav"' not in html
+    assert 'name="source" value="footer"' not in html
 
 
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