Migrate contentjson and badjson to library &

Add omitempty in format

option/inbound.go

@@ -3,9 +3,9 @@ package option
 import (
 	"time"
 
-	"github.com/sagernet/sing-box/common/json"
 	C "github.com/sagernet/sing-box/constant"
 	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/json"
 )
 
 type _Inbound struct {
@@ -116,7 +116,7 @@ func (h *Inbound) UnmarshalJSON(bytes []byte) error {
 	}
 	err = UnmarshallExcluded(bytes, (*_Inbound)(h), v)
 	if err != nil {
-		return E.Cause(err, "inbound options")
+		return err
 	}
 	return nil
 }