refactor(dctx): sort table columns and indexes for deterministic output

pkg/writers/dctx/writer.go

@@ -4,6 +4,7 @@ import (
 	"encoding/xml"
 	"fmt"
 	"os"
+	"sort"
 	"strings"
 
 	"github.com/google/uuid"
@@ -155,8 +156,15 @@ func (w *Writer) mapTableFields(table *models.Table) models.DCTXTable {
 		},
 	}
 
+	columnNames := make([]string, 0, len(table.Columns))
+	for name := range table.Columns {
+		columnNames = append(columnNames, name)
+	}
+	sort.Strings(columnNames)
+
 	i := 0
-	for _, column := range table.Columns {
+	for _, colName := range columnNames {
+		column := table.Columns[colName]
 		dctxTable.Fields[i] = w.mapField(column)
 		i++
 	}
@@ -165,12 +173,27 @@ func (w *Writer) mapTableFields(table *models.Table) models.DCTXTable {
 }
 
 func (w *Writer) mapTableKeys(table *models.Table) []models.DCTXKey {
-	keys := make([]models.DCTXKey, len(table.Indexes))
-	i := 0
+	indexes := make([]*models.Index, 0, len(table.Indexes))
 	for _, index := range table.Indexes {
-		keys[i] = w.mapKey(index, table)
-		i++
+		indexes = append(indexes, index)
 	}
+
+	// Stable ordering for deterministic output and test reproducibility:
+	// primary keys first, then lexicographic by index name.
+	sort.Slice(indexes, func(i, j int) bool {
+		iPrimary := strings.HasSuffix(indexes[i].Name, "_pkey")
+		jPrimary := strings.HasSuffix(indexes[j].Name, "_pkey")
+		if iPrimary != jPrimary {
+			return iPrimary
+		}
+		return indexes[i].Name < indexes[j].Name
+	})
+
+	keys := make([]models.DCTXKey, len(indexes))
+	for i, index := range indexes {
+		keys[i] = w.mapKey(index, table)
+	}
+
 	return keys
 }