feat(legal): add /policies, /contact, /promotions for Stripe verification

Adds the consolidated Customer Policies doc covering customer service contact,
return / refund / dispute policy, cancellation policy, U.S. legal and export
restrictions, and promotional terms. Companion /contact page surfaces the
business phone (470) 949-4131 alongside the support/sales/billing/security
inboxes and target response SLAs. /promotions page exists as a stub so the
cross-reference in Policies §6.2 is live; it states no promotions are
currently active and will be appended to when offers run.

Refresh Privacy and Terms footers to point at /contact + /policies and drop
the stale hello@ mailto. Landing footer now exposes Privacy / Terms /
Policies / Contact links so Stripe's site review can reach them in one hop
from the marketing surface.

Mailing address is deferred until a P.O. Box is set up — left as an
in-source TODO and displayed publicly as "available on request" so we
don't ship a placeholder address.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/pages/TermsPage.tsx

@@ -39,7 +39,7 @@ export default function TermsPage() {
 
             <section>
               <h2 className="text-xl font-semibold text-foreground mb-3">6. Contact</h2>
-              <p>Questions about these terms? Email us at <a href="mailto:hello@resolutionflow.com" className="text-primary hover:underline">hello@resolutionflow.com</a>.</p>
+              <p>Questions about these terms? Email <a href="mailto:support@resolutionflow.com" className="text-primary hover:underline">support@resolutionflow.com</a> or visit our <Link to="/contact" className="text-primary hover:underline">contact page</Link>. Billing, cancellation, refund, and promotional terms are governed by our <Link to="/policies" className="text-primary hover:underline">Customer Policies</Link>.</p>
             </section>
           </div>
         </div>