v0.2.1

• Non-finite doubles. Firestore encodes NaN, Infinity and -Infinity as
  strings in REST values; the codec now writes them in that form instead of
  emitting invalid JSON, and reads them back as Dart doubles.
• signIn awaits exchangeCode inside its try block. Same behavior, and it
  clears unawaited_return_in_try_block under Dart 3.13.1's analyzer.