feat: Add crypto, getRandomString

lib/util/getRandomString.ts

@@ -0,0 +1,11 @@
+import { RandomString } from "../config/configTypes"
+import { getRandomCharInSet } from "./getRandomCharInSet"
+
+export function getRandomString(generator: RandomString): string {
+  let s = ""
+  for (let i = 0; i < generator.len; i++) {
+    s = s + getRandomCharInSet(generator.charset)
+  }
+
+  return s
+}