init receiver ui with react

EnvelopeGenerator.Web/Client/receiver-ui-react/src/utils/Utils.js

@@ -0,0 +1,27 @@
+export function blobToURL(blob) {
+  return new Promise((resolve) => {
+    const reader = new FileReader();
+    reader.readAsDataURL(blob);
+    reader.onloadend = function () {
+      const base64data = reader.result;
+      resolve(base64data);
+    };
+  });
+}
+
+export async function fileToBlob(file, handleUpdate) {
+  const { content, size } = file;
+  let chunks = [];
+  let i = 0;
+  const totalCount = Math.round(size / 250000);
+
+  for await (const chunk of content) {
+    if (handleUpdate) {
+      handleUpdate(i, totalCount);
+    }
+    chunks.push(chunk);
+    i++;
+  }
+  // eslint-disable-next-line no-undef
+  return new Blob(chunks);
+}