Keep quoted empty trailing field with trailingDelimiter

[rootvector2]

addRecordValue drops the empty last field whenever the format's trailingDelimiter is enabled, checking only that the trimmed value is empty. A quoted empty field at the end of a record is a real value, not a trailing delimiter, so a,b,"" parsed with setTrailingDelimiter(true) came back as two values [a, b] instead of three [a, b, ""]. The unquoted case a,b, is a genuine trailing delimiter and still collapses to two fields. Fixed by only dropping the field when the token is unquoted; reusableToken.isQuoted is already tracked and used by handleNull.

Found while round-tripping records that contain an explicit empty quoted field.

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[garydgregory]

Thank you for your update.
Would you please update the Javadoc for "trailing delimiter" to explain the behavior. Especially contrasting with "trailing data".
TY!

[rootvector2]

Done. Expanded the Javadoc on setTrailingDelimiter/getTrailingDelimiter to cover the write side (delimiter appended after the last value) and the read side (the empty field it produces is dropped, but a quoted empty trailing field "" is kept). Also noted it's unrelated to trailingData, which is about characters after a closing quote.

[garydgregory]

TY @rootvector2 , merged 🚀