feat: enforce browser security boundaries

src/presentation/security/safe-text.jsx

@@ -0,0 +1,9 @@
+/**
+ * Untrusted content is rendered as a React text node. HTML interpretation is
+ * intentionally not offered by this template.
+ *
+ * @param {{ value: unknown }} props
+ */
+export function SafeText({ value }) {
+  return <span>{typeof value === "string" ? value : String(value ?? "")}</span>;
+}