feat(legal): add /policies, /contact, /promotions pages + MarketingFooter (#165)

Adds the three legal/contact pages needed for Stripe live-mode site review: /policies (consolidated customer policies — refunds, cancellation, legal restrictions, promotions), /contact (phone (470) 949-4131 + support/sales/billing/security inboxes), /promotions (stub satisfying §6.2 cross-ref).

Extracts the existing landing footer into components/common/MarketingFooter.tsx and mounts it on /pricing and /contact-sales so all four legal links are reachable from every marketing surface.

Privacy and Terms closing sections updated to point at /contact + /policies; stale hello@ mailto removed.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Co-authored-by: Michael Chihlas <michael@resolutionflow.com>
Co-committed-by: Michael Chihlas <michael@resolutionflow.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>