Run D&D spell lanes through typed artifacts

internal/framework/pipeline/merger_registry.go

@@ -1,6 +1,7 @@
 package pipeline
 
 import (
+	"context"
 	"fmt"
 	"reflect"
 	"strings"
@@ -28,6 +29,7 @@ type typedMergerEntry struct {
 	valueType       reflect.Type
 	validateOptions OptionValidator
 	builder         func(BuildRequest) (any, error)
+	merge           typedMergeOperation
 }
 
 func NewMergerRegistry() *MergerRegistry {
@@ -127,6 +129,25 @@ func RegisterMergerBuilder[T any](registry *MergerRegistry, spec ModuleSpec, val
 		builder: func(request BuildRequest) (any, error) {
 			return builder(cloneBuildRequest(request))
 		},
+		merge: func(ctx context.Context, implementation any, request contracts.TypedMergeRequest[any]) (erasedTypedResult, error) {
+			merger, ok := implementation.(contracts.Merger[T])
+			if !ok {
+				return erasedTypedResult{}, fmt.Errorf("merger %q has incompatible implementation %T", normalizedSpec.Key, implementation)
+			}
+			outputs := make([]contracts.ExtractArtifact[T], len(request.ExtractOutputs))
+			for i, output := range request.ExtractOutputs {
+				value, err := exactTypedValue[T]("merge extract value", output.Value)
+				if err != nil {
+					return erasedTypedResult{}, err
+				}
+				outputs[i] = contracts.ExtractArtifact[T]{LaneID: output.LaneID, ExtractorKey: output.ExtractorKey, SourceID: output.SourceID, ChunkID: output.ChunkID, ChunkIndex: output.ChunkIndex, ChunkRef: output.ChunkRef, Value: value}
+			}
+			result, err := merger.Merge(ctx, contracts.TypedMergeRequest[T]{Source: request.Source, LaneID: request.LaneID, ExtractOutputs: outputs, SourceInput: request.SourceInput, SessionID: request.SessionID, References: request.References, LLMProfile: request.LLMProfile, Metadata: request.Metadata})
+			if err != nil {
+				return erasedTypedResult{}, err
+			}
+			return erasedTypedResult{Value: result.Value, Warnings: result.Warnings}, nil
+		},
 	}
 	return nil
 }