fix(bf-pages): restore ODOO Bootcamp footer link; add HOST27 to the BF block

Both pages shipped (355c5d0) with a three-item footer; the site footer is a
four-item commitment. The /odoo-erp-automation-bootcamp/ entry is restored on
both pages, matching index.html / odoo-hosting-2027.html.

/odoo-hosting-offers/: the code HOST27 is added inside the date-scoped Black
Friday block only (BF-BLOCK-START..END), so it disappears with the block after
30 Nov. Title, meta description and H1 are untouched — the intent split holds.

verify-html.py: PROBLEMS 0. node --check script.js: OK.

odoo-black-friday/index.html

@@ -579,6 +579,7 @@
           <div>
             <h4>Useful Links</h4>
             <ul>
+              <li><a href="/odoo-erp-automation-bootcamp/">ODOO Bootcamp</a></li>
               <li><a href="/odoo-hosting-2027.html">ODOO Hosting in 2027</a></li>
               <li><a href="/support.html">Support</a></li>
               <li><a href="/legal.html">Legal</a></li>