“The only solution is to enforce vagrancy laws, clean up the streets, and send hardcore homeless to some kind of local government detention”
Cleaning up the streets you can do, but the Supreme Court is not going to allow you to arrest people just for “vagrancy” or send them to detention camps. It’s not constitutional.
You can get around that maybe by charging them with other offenses, because they probably commit plenty of legitimate ones, like drug offenses, or “aggressive panhandling”, theft, etc, but you can’t just say, basically, “you exist and I don’t like looking at you, go to jail”.
SCOTUS has ruled against police have broad discretion to arrest people for "vagrancy" if it merely involves them walking down the street, or standing on street-corners, etc...
what about pitching tents or sleeping on public property? Urinating in public? leaving trash and waste? using or selling drugs?