SAN FRANCISCO — President Joe Biden’s administration announced Monday that it is ramping up efforts to help house people now sleeping on sidewalks and in tents and cars as a new federal report confirms what’s obvious to people in many cities: Homelessness is persisting despite increased local efforts. It was up by about 2,000 people — an increase of less than 1%. The 2022 All In strategy roadmap made public Monday follows a 2010 effort called Opening Doors, which was the nation’s first comprehensive strategy seeking to prevent and end homelessness.