feat: harden portfolio and add SEO foundations

app/components/story/NotebookBrowser.tsx

@@ -176,13 +176,26 @@ export default function NotebookBrowser({
                 <li key={technology}>{technology}</li>
               ))}
             </ul>
-            <a
-              href={selectedProject.demoUrl}
-              rel="noopener noreferrer"
-              target="_blank"
-            >
-              Abrir projeto <span aria-hidden="true">↗</span>
-            </a>
+            {selectedProject.demoAvailability === "unavailable" ? (
+              <span aria-disabled="true">
+                Demo indisponível na última verificação
+              </span>
+            ) : selectedProject.demoAvailability === "none" ||
+              !selectedProject.demoUrl ? null : (
+              <a
+                href={selectedProject.demoUrl}
+                rel="noopener noreferrer"
+                target="_blank"
+              >
+                Abrir projeto <span aria-hidden="true">↗</span>
+                {selectedProject.demoAvailability === "unknown" ? (
+                  <span className="sr-only">
+                    {" "}
+                    Disponibilidade não verificada
+                  </span>
+                ) : null}
+              </a>
+            )}
           </div>
 
           <div className="notebook-screenshot-wrap">