fix(marketing): A-2.7b WCAG 2.2 AA polish + JSON-LD test hardening

- Drop role="region" from FAQ panels (had no accessible name — axe-core
  violation; disclosure pattern with button + aria-controls + aria-expanded
  is sufficient per WAI-APG accordion guidance)
- Add focus-visible:outline-2 outline-brand-b1 outline-offset-2 to FAQ
  buttons (WCAG 2.2 AA 2.4.7 Focus Not Obscured + 2.4.11 Focus Appearance —
  Safari default focus indicator is unreliable)
- Sweep pre-existing text-white/50 on Hero social proof microcopy → /70
  (branch-wide WCAG floor; recurring landmine flagged at A-2.7a review)
- Strengthen test_faq_jsonld_schema_present to json.loads() the extracted
  block and validate the FAQPage schema shape (regression guard for future
  content edits with unescaped backslashes/quotes)

tests/test_marketing_landing_template.py

@@ -696,6 +696,23 @@ def test_faq_jsonld_schema_present():
     assert '&nbsp;' not in body[body.find('"FAQPage"'):body.find('</script>', body.find('"FAQPage"'))], \
         "JSON-LD must not contain raw '&nbsp;' entities — strip them server-side"
 
+    # M-1 hardening: actually parse the JSON-LD to catch malformed JSON regressions
+    import json
+    import re
+    match = re.search(r'<script type="application/ld\+json">(.*?)</script>',
+                      body, re.DOTALL)
+    assert match, "JSON-LD block not found"
+    parsed = json.loads(match.group(1))
+    assert parsed['@context'] == 'https://schema.org'
+    assert parsed['@type'] == 'FAQPage'
+    assert isinstance(parsed['mainEntity'], list)
+    assert len(parsed['mainEntity']) == 7, "FAQPage must contain exactly 7 questions"
+    for q in parsed['mainEntity']:
+        assert q['@type'] == 'Question'
+        assert q['acceptedAnswer']['@type'] == 'Answer'
+        assert q['name'].strip(), "Question name must not be empty"
+        assert q['acceptedAnswer']['text'].strip(), "Answer text must not be empty"
+
 
 def test_cta_final_section():
     """CTA final section with mailto pré-inscription + ghost button to #tarifs."""