Migrate utils to ts

app/src/utils/formatBytes.ts

@@ -0,0 +1,24 @@
+/**
+ * Units for file size display.
+ */
+type ByteUnit = 'B' | 'KB' | 'MB' | 'GB';
+
+/**
+ * An array of size units in ascending order.
+ */
+const UNITS: readonly ByteUnit[] = ['B', 'KB', 'MB', 'GB'] as const;
+
+/**
+ * Formats a number of bytes into a human-readable string.
+ * @param bytes - The number of bytes to format.
+ * @returns A string representing the formatted file size.
+ */
+export const formatBytes = (bytes: number): string => {
+  let size: number = bytes;
+  let unitIndex: number = 0;
+  while (size >= 1024 && unitIndex < UNITS.length - 1) {
+    size /= 1024;
+    unitIndex++;
+  }
+  return `${size.toFixed(1)} ${UNITS[unitIndex]}`;
+};