fix: add missing site-footer component and remove brand-icons dependency

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/site-footer.tsx

@@ -0,0 +1,34 @@
+import { appConfig } from "@/lib/config"
+
+export function SiteFooter() {
+  return (
+    <footer className="border-t py-6 md:py-0">
+      <div className="container flex flex-col items-center justify-between gap-4 md:h-14 md:flex-row">
+        <p className="text-center text-sm leading-loose text-muted-foreground md:text-left">
+          © {new Date().getFullYear()} {appConfig.name}. Todos os direitos reservados.
+        </p>
+        {(appConfig.supportEmail || appConfig.supportWhatsapp) && (
+          <p className="text-center text-sm text-muted-foreground md:text-right">
+            Suporte:{" "}
+            {appConfig.supportEmail && (
+              <a href={`mailto:${appConfig.supportEmail}`} className="underline underline-offset-4 hover:text-foreground">
+                {appConfig.supportEmail}
+              </a>
+            )}
+            {appConfig.supportEmail && appConfig.supportWhatsapp && " · "}
+            {appConfig.supportWhatsapp && (
+              <a
+                href={`https://wa.me/${appConfig.supportWhatsapp}`}
+                target="_blank"
+                rel="noreferrer"
+                className="underline underline-offset-4 hover:text-foreground"
+              >
+                WhatsApp
+              </a>
+            )}
+          </p>
+        )}
+      </div>
+    </footer>
+  )
+}