Implemented an overlap detection module in the postprocessing chain

internal/builtin/postprocess.go

@@ -7,6 +7,7 @@ import (
 	"gitea.maximumdirect.net/eric/seriatim/internal/autocorrect"
 	"gitea.maximumdirect.net/eric/seriatim/internal/config"
 	"gitea.maximumdirect.net/eric/seriatim/internal/model"
+	"gitea.maximumdirect.net/eric/seriatim/internal/overlap"
 	"gitea.maximumdirect.net/eric/seriatim/internal/report"
 )
 
@@ -48,6 +49,23 @@ func (assignIDs) Process(ctx context.Context, in model.MergedTranscript, cfg con
 	}, nil
 }
 
+type detectOverlaps struct{}
+
+func (detectOverlaps) Name() string {
+	return "detect-overlaps"
+}
+
+func (detectOverlaps) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
+	if err := ctx.Err(); err != nil {
+		return model.MergedTranscript{}, nil, err
+	}
+
+	in = overlap.Detect(in)
+	return in, []report.Event{
+		report.Info("postprocessing", "detect-overlaps", fmt.Sprintf("detected %d overlap group(s)", len(in.OverlapGroups))),
+	}, nil
+}
+
 type autocorrectPostprocessor struct{}
 
 func (autocorrectPostprocessor) Name() string {