UVALDE, Texas — Manuel and Patricia Oliver had already been on the road for more than a week when they pulled their school bus bearing an American flag into a city park in Uvalde. They were unsure of just how many people would greet them on that sweltering day. Then the families started arriving. Parents, grandparents, siblings and other kin of some of the 22 people killed last year at Robb Elementary streamed into the park, embracing the Olivers and each other. So, too, did a woman who lost her