feat: integrate Stripe checkout links on pricing page

Added Stripe Payment Links for Pro and Team plans:
- Pro: Sandbox checkout link
- Team: Sandbox checkout link

Author: Test

docs/pricing.html

@@ -303,7 +303,7 @@ <h1>Simple, Transparent Pricing</h1>
             <li>Custom prompts library</li>
             <li>Email support</li>
         </ul>
-        <a href="/live" class="plan-cta primary">Start Free Trial →</a>
+        <a href="https://buy.stripe.com/test_14AfZgcwl4m7frb8c74F200" class="plan-cta primary">Subscribe to Pro →</a>
     </div>
 
     <!-- Team Tier -->
@@ -324,7 +324,7 @@ <h1>Simple, Transparent Pricing</h1>
             <li>Audit logs</li>
             <li>Dedicated support</li>
         </ul>
-        <a href="/contact" class="plan-cta secondary">Contact Sales →</a>
+        <a href="https://buy.stripe.com/test_dRm14m0NDg4PbaVgID4F201" class="plan-cta secondary">Subscribe to Team →</a>
     </div>
 </div>