fix: add missing code

Author: shanejonas

openrpc.json

@@ -0,0 +1,24 @@
+const openRPCDocument = {
+    openrpc: '1.2.4',
+    info: {
+        title: 'Shardeum JSON RPC',
+        version: '1.0',
+        description: 'Shardeum JSON RPC',
+        contact: {
+            name: 'Shardeum',
+            url: 'https://shardeum.org',
+        }
+    },
+    servers: [
+        {
+            url: 'https://api.shardeum.org',
+        }
+    ],
+    methods: []
+}
+
+const rpcDiscover = async (): Promise<unknown> => {
+  return openRPCDocument
+}
+
+export default rpcDiscover