Chore: remove unused key-value attribute feature (#3076)

Co-authored-by: Loyalsoldier <10487845+Loyalsoldier@users.noreply.github.com>

main.go

@@ -8,7 +8,6 @@ import (
 	"path/filepath"
 	"regexp"
 	"sort"
-	"strconv"
 	"strings"
 
 	router "github.com/v2fly/v2ray-core/v5/app/router/routercommon"
@@ -161,20 +160,8 @@ func parseAttribute(attr string) (*router.Domain_Attribute, error) {
 		return &attribute, fmt.Errorf("invalid attribute: %s", attr)
 	}
 
-	// Trim attribute prefix `@` character
-	attr = attr[1:]
-	parts := strings.Split(attr, "=")
-	if len(parts) == 1 {
-		attribute.Key = strings.ToLower(parts[0])
-		attribute.TypedValue = &router.Domain_Attribute_BoolValue{BoolValue: true}
-	} else {
-		attribute.Key = strings.ToLower(parts[0])
-		intv, err := strconv.Atoi(parts[1])
-		if err != nil {
-			return &attribute, fmt.Errorf("invalid attribute: %s: %v", attr, err)
-		}
-		attribute.TypedValue = &router.Domain_Attribute_IntValue{IntValue: int64(intv)}
-	}
+	attribute.Key = strings.ToLower(attr[1:]) // Trim attribute prefix `@` character
+	attribute.TypedValue = &router.Domain_Attribute_BoolValue{BoolValue: true}
 	return &attribute, nil
 }