feat: add format setting for completion

converter/constant/format.go

@@ -1,8 +1,31 @@
 package constant
 
-type ConversionFormat string
+import "github.com/thediveo/enumflag/v2"
+
+type ConversionFormat enumflag.Flag
 
 const (
-	ImageFormatWebP    ConversionFormat = "webp"
-	ImageFormatUnknown ConversionFormat = ""
+	WebP ConversionFormat = iota
 )
+
+var CommandValue = map[ConversionFormat][]string{
+	WebP: {"webp"},
+}
+
+var HelpText = enumflag.Help[ConversionFormat]{
+	WebP: "WebP Image Format",
+}
+
+var DefaultConversion = WebP
+
+func (c ConversionFormat) String() string {
+	return CommandValue[c][0]
+}
+
+func ListAll() []string {
+	var formats []string
+	for _, names := range CommandValue {
+		formats = append(formats, names[0])
+	}
+	return formats
+}