The most visible damage from fires that lit up Napa Valley hillsides in October 2017 are random black in the treeline, most of them miles from wineries. To the west in Sonoma County nothing is visible from the fall’s two weeks of post-harvest smoke. While some homeowners are rebuilding, tourists see nearly nothing but a vibrant, welcoming scene in this wine country 50 miles north of San Francisco. We proved it to ourselves in a late winter visit – season of lower prices –to Healdsburg, the cultural hub of Sonoma County. Travelers, it seems, often choose just one wine country, Sonoma or Napa. The choice is based on the time available for touring the collective 600-plus wineries or maybe by the type of wine…