feat(adapter): registry with detect filtering and duplicate guard

internal/render/json.go

@@ -0,0 +1,18 @@
+// Package render holds deterministic format marshallers.
+package render
+
+import (
+	"bytes"
+	"encoding/json"
+)
+
+func JSON(v any) ([]byte, error) {
+	var buf bytes.Buffer
+	enc := json.NewEncoder(&buf)
+	enc.SetIndent("", "  ")
+	enc.SetEscapeHTML(false)
+	if err := enc.Encode(v); err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}

internal/render/render_test.go

@@ -0,0 +1,28 @@
+package render
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestJSONIndent(t *testing.T) {
+	b, err := JSON(map[string]any{"a": 1, "b": "x"})
+	require.NoError(t, err)
+	s := string(b)
+	assert.Contains(t, s, "\"a\": 1")
+	assert.True(t, s[len(s)-1] == '\n', "trailing newline required")
+}
+
+func TestYAML(t *testing.T) {
+	b, err := YAML(map[string]any{"a": 1})
+	require.NoError(t, err)
+	assert.Contains(t, string(b), "a: 1")
+}
+
+func TestTOML(t *testing.T) {
+	b, err := TOML(map[string]any{"a": 1})
+	require.NoError(t, err)
+	assert.Contains(t, string(b), "a = 1")
+}

internal/render/toml.go

@@ -0,0 +1,7 @@
+package render
+
+import "github.com/pelletier/go-toml/v2"
+
+func TOML(v any) ([]byte, error) {
+	return toml.Marshal(v)
+}

internal/render/yaml.go

@@ -0,0 +1,7 @@
+package render
+
+import "gopkg.in/yaml.v3"
+
+func YAML(v any) ([]byte, error) {
+	return yaml.Marshal(v)
+}