implemented ordering preservation

test/builder_multifile_test.go

@@ -18,7 +18,7 @@ func TestMultiFileBuildMergeAndOrder(t *testing.T) {
 	// File 1: Has FieldA, no Class.
 	// File 2: Has Class, FieldB.
 	// Both in package +MyObj
-	
+
 	f1Content := `
 #package Proj.+MyObj
 FieldA = 10
@@ -30,10 +30,10 @@ FieldB = 20
 `
 	os.WriteFile("build_multi_test/f1.marte", []byte(f1Content), 0644)
 	os.WriteFile("build_multi_test/f2.marte", []byte(f2Content), 0644)
-	
+
 	// Execute Build
 	b := builder.NewBuilder([]string{"build_multi_test/f1.marte", "build_multi_test/f2.marte"})
-	
+
 	// Prepare output file
 	// Should be +MyObj.marte (normalized MyObj.marte) - Actually checking content
 	outputFile := "build_multi_test/MyObj.marte"
@@ -48,19 +48,19 @@ FieldB = 20
 		t.Fatalf("Build failed: %v", err)
 	}
 	f.Close() // Close to flush
-	
+
 	// Check Output
 	if _, err := os.Stat(outputFile); os.IsNotExist(err) {
 		t.Fatalf("Expected output file not found")
 	}
-	
+
 	content, err := os.ReadFile(outputFile)
 	if err != nil {
 		t.Fatalf("Failed to read output: %v", err)
 	}
-	
+
 	output := string(content)
-	
+
 	// Check presence
 	if !strings.Contains(output, "Class = \"MyClass\"") {
 		t.Error("Output missing Class")
@@ -71,23 +71,23 @@ FieldB = 20
 	if !strings.Contains(output, "FieldB = 20") {
 		t.Error("Output missing FieldB")
 	}
-	
+
 	// Check Order: Class/FieldB (from f2) should come BEFORE FieldA (from f1)
 	// because f2 has the Class definition.
-	
+
 	idxClass := strings.Index(output, "Class")
 	idxFieldB := strings.Index(output, "FieldB")
 	idxFieldA := strings.Index(output, "FieldA")
-	
+
 	if idxClass == -1 || idxFieldB == -1 || idxFieldA == -1 {
 		t.Fatal("Missing fields in output")
 	}
-	
+
 	// Class should be first
 	if idxClass > idxFieldA {
 		t.Errorf("Expected Class (from f2) to be before FieldA (from f1). Output:\n%s", output)
 	}
-	
+
 	// FieldB should be near Class (same fragment)
 	// FieldA should be after
 	if idxFieldB > idxFieldA {