The Biden administration finalized nursing home staffing rules Monday that will require thousands of them to hire more nurses and aides — while giving them years to do so. The new rules from the Centers for Medicare & Medicaid Services are the most substantial changes to federal oversight of the nation’s roughly 15,000 nursing homes in more than three decades. But they are less stringent than what patient advocates said was needed to provide high-quality care. Spurred by disproportionate deaths from covid-19 in long-term care facilities, the rules aim to address perennially sparse staffing tha…