As several hundred people meandered through the crowded maze of vendors inside South Richmond’s Plant Zero, Vanessa Alsondo didn’t seem to mind the commotion. Her fingers were in constant motion, even at times when her attention was elsewhere, as she crocheted a bag she hoped to finish by the end of yesterday’s Spring Bada Bing. “If I don’t run into any mistakes, I’ll have a bag when I’m done,“ said Alsondo, owner and designer of Ninnycat Crochet.