SAN DIEGO — The first day that asylum seekers could make appointments through their smartphones to request protection at U.S. ports of entry, a 22-year-old mother and her three children in Tijuana rushed to try to secure their own place in the digital line. More than three months later, she and thousands of other asylum seekers waiting in Mexico are still trying. Though the pandemic-era policy that created this smartphone appointment process — Title 42 — is set to end Thursday, asylum seekers’ experiences aren’t likely to change anytime soon.