fix(bf): strip the last off-panel mentions of the discount code

The code may not be named where a visitor or crawler can read it before
opening a reveal panel. Three off-panel leaks removed:

- /odoo-black-friday/ FAQ (visible answer + its FAQPage JSON-LD twin,
  byte-identical): 'the code stops working' -> 'the offer stops working'.
- /odoo-hosting-offers/ og:image:alt: the trailing ', and the code
  HOST27' dropped; the offer and the 16-30 November window stay.
- /odoo-hosting-offers/ date-scoped Black Friday block: the line no
  longer names the code; it states the offer and links to
  /odoo-black-friday/ (the only page with a reveal panel), marked with a
  dated comment for removal after 30 November 2026.

HOST27 now survives only inside the .bf-panel on /odoo-black-friday/;
/odoo-hosting-offers/ carries zero.

odoo-black-friday/index.html

@@ -480,7 +480,7 @@
                 "name": "What happens if I miss the deadline?",
                 "acceptedAnswer": {
                   "@type": "Answer",
-                  "text": "The price goes back to normal on 1 December 2026 and the code stops working. It returns with next year's offer."
+                  "text": "The price goes back to normal on 1 December 2026 and the offer stops working. It returns with next year's offer."
                 }
               }
             ]
@@ -598,7 +598,7 @@
           </details>
           <details class="cmp-faq">
             <summary class="plausible-event-name=FAQ">What happens if I miss the deadline?</summary>
-            <div class="faq-a"><p>The price goes back to normal on 1 December 2026 and the code stops working. It returns with next year's offer.</p></div>
+            <div class="faq-a"><p>The price goes back to normal on 1 December 2026 and the offer stops working. It returns with next year's offer.</p></div>
           </details>
         </div>