randomId function
Generates a random String id Adopted from: https://github.com/ai/nanoid/blob/main/non-secure/index.js
Implementation
String randomId({int size = 21}) {
final id = StringBuffer();
for (var i = 0; i < size; i++) {
id.write(_alphabet[(math.Random().nextDouble() * 64).floor() | 0]);
}
return id.toString();
}