Congregational worship music has plenty of variety these days. Depending on the church, you could hear traditional hymns, a gospel choir, or arena rock. What’s harder to find on a typical Sunday morning is a jazz quartet. For many of us, jazz music is reserved for smoky nightclubs or public-radio broadcasts. That’s why pianist/singer Deanna Witkowski is something of an anomaly. She’s a musician who feels as much at home in a secular club as an evangelical sanctuary.