message: fix: segfault in coordinate mapper due to out-of-bounds array access
diff: @@ -27,8 +27,12 @@ namespace {
  int refPos = 0;
  for (int i = 0; i < alnLength; ++i) {
  if (ref[i] == Nucleotide::GAP) {
  + if (revCoordMap.empty()) {
  + revCoordMap.push_back(0);
  + } else {
  const auto& prev = revCoordMap.back();
  revCoordMap.push_back(prev);
  + }
  } else {
  revCoordMap.push_back(refPos);
  ++refPos;
  