Your constitutional rights are in no way being violated. Case law has establish the peramiters of what is and is not acceptable. The Patrol enforces Federal law and the Martinez-Fuerte case was found to be constitutional and necessary to establish citizenship. There are countless instances of case law that guide the constitutionality of Federal Law Enforcement. I conceded that it can be inconvenient to have to establish citizenship as is the reality that some people just don't like LEO interaction. All traffic stops are done with reasonal suspicion with articulable reasons. They are not done for no good reason. I understand where you are coming from because it is frustrating however you have to see it from the Agents view point. Benign things for the public are indicators for a Good and attentive Agent.
Good find Vintagearms!. Was just going to cite that case
"Apathy is the glove into which evil slips its hand." -Bodie Thoene