I resolved the probleme by installing ionic 2.2.3 and cordova 6.5.0 by excuting the command :
npm install -g ionic @2.2.3 firstname.lastname@example.org
but first of all you have to uninstall the previos version of ionic and cordova installed on you computer, you have just to execut this command :
npm uninstall cordova ionic
thank you and good luck
sorry for the delay in answering, it's been some crazy months lately.
The siteurl should work fine with Ionic 3, at least it does for us. I recommend leaving the repo as it is and try to install the app in the device, to check if it works that way. If it doesn't then it's not siteurl's fault