fix: vfox upgrade unable to detect current version (#556)

* Initial plan

* Fix vfox upgrade command to correctly detect current version

Co-authored-by: aooohan <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: aooohan <[email protected]>

Author: Copilot

cmd/commands/upgrade.go

@@ -116,7 +116,7 @@ func upgradeCmd(ctx context.Context, cmd *cli.Command) error {
 	defer manager.Close()
 	httpClient := manager.HttpClient()
 
-	currVersion := fmt.Sprintf("v%s", cmd.Version)
+	currVersion := fmt.Sprintf("v%s", internal.RuntimeVersion)
 	latestVersion, err := fetchLatestVersion(httpClient)
 	if err != nil {
 		return cli.Exit("Failed to fetch the latest version: "+err.Error(), 1)