xrpl.js has setTransactionFlagsToNumber() to convert flags from a map of names to an integer, and parseAccountRootFlags() for going from an AccountRoot object's flags integer to a map of booleans, but there's no helper to parse transaction flags from an integer into a map of booleans.

This is a common point of confusion for new XRPL devs, who don't know for example why, for example, this transaction has "Flags":2148007936 when there is no flag with the value 2148007936. (It's actually the combination of two flags, tfSell and tfFullyCanonicalSig.)

I suggest adding a parseTransactionFlags(transaction) method that returns a map of flag names with booleans, e.g.:

{
  "tfSell": true,
  "tfFullyCanonicalSig": true
}

I'm ambivalent about whether it should include flags with the value false (meaning, ones that are valid for this transaction type but not enabled).