feat(09-10): add typed relation manager

pact/capabilities.go

@@ -192,6 +192,13 @@ type ListExtendQuery interface {
 	ListExtendQuery(ctx context.Context, db *gorm.DB) *gorm.DB
 }
 
+// ListRelationColumnMapper maps a source-schema relation column onto the
+// physical column exposed by the related Go model. It supports legacy admin
+// schemas whose public field names no longer match the database schema.
+type ListRelationColumnMapper interface {
+	ListRelationColumn(relation, column string) (string, bool)
+}
+
 // FormExtendQuery optionally narrows admin form record lookup.
 type FormExtendQuery interface {
 	FormExtendQuery(ctx context.Context, db *gorm.DB) *gorm.DB