feat: custom json marshaler implementation

pkg/json/map.go

@@ -0,0 +1,24 @@
+package json
+
+import (
+	"reflect"
+)
+
+type Map[V any] map[string]V
+
+func (m Map[V]) MarshalJSONTo(buf []byte) []byte {
+	buf = append(buf, '{')
+	i := 0
+	n := len(m)
+	for k, v := range m {
+		buf = AppendString(buf, k)
+		buf = append(buf, ':')
+		buf = appendMarshal(reflect.ValueOf(v), buf)
+		if i != n-1 {
+			buf = append(buf, ',')
+		}
+		i++
+	}
+	buf = append(buf, '}')
+	return buf
+}