chore: import upstream snapshot with attribution

apps/sim/app/(landing)/components/json-ld/index.ts

@@ -0,0 +1,2 @@
+export type { JsonLdData } from './json-ld'
+export { JsonLd } from './json-ld'

apps/sim/app/(landing)/components/json-ld/json-ld.tsx

@@ -0,0 +1,50 @@
+import type { ReactElement } from 'react'
+
+/**
+ * Characters that break out of an inline HTML `<script>` context, mapped to
+ * their unicode escapes. `<` is the dangerous one (`</script>`); `>` and `&` are
+ * escaped for completeness, and the JS line/paragraph separators (U+2028/U+2029)
+ * keep the payload valid inside inline scripts.
+ */
+const HTML_ESCAPES: Record<string, string> = {
+  '<': '\\u003c',
+  '>': '\\u003e',
+  '&': '\\u0026',
+  [String.fromCharCode(0x2028)]: '\\u2028',
+  [String.fromCharCode(0x2029)]: '\\u2029',
+}
+
+const UNSAFE_HTML_CHARS = new RegExp(`[<>&${String.fromCharCode(0x2028, 0x2029)}]`, 'g')
+
+/**
+ * Serialize structured data for an inline `application/ld+json` script. Plain
+ * `JSON.stringify` does not HTML-escape, so a `</script>` (or stray `<`) in the
+ * data would break out of the script tag and become an XSS sink. Escaping these
+ * characters as unicode escapes keeps the JSON valid and semantically identical,
+ * so crawlers read the exact same graph — SEO output is unchanged.
+ */
+function serializeJsonLd(data: JsonLdData): string {
+  return JSON.stringify(data).replace(UNSAFE_HTML_CHARS, (char) => HTML_ESCAPES[char])
+}
+
+export type JsonLdData = Record<string, unknown>
+
+interface JsonLdProps {
+  data: JsonLdData
+}
+
+/**
+ * Server-rendered JSON-LD `<script>`. The single source of truth for emitting
+ * structured data across the landing surface — every page/section passes its
+ * schema graph as `data` and this owns the safe serialization. Render it in a
+ * Server Component before visible content so crawlers and AI answer engines read
+ * the graph first.
+ */
+export function JsonLd({ data }: JsonLdProps): ReactElement {
+  return (
+    <script
+      type='application/ld+json'
+      dangerouslySetInnerHTML={{ __html: serializeJsonLd(data) }}
+    />
+  )
+}