src/data/markets-registry.ts — 25 cities (NYC, LA, Chicago, Houston, Phoenix, Nashville, Denver, Miami, Seattle, Atlanta, Dallas, SF, Boston, Philly, San Diego, Minneapolis, Portland, Charlotte, San Antonio, Columbus, Raleigh, Tampa, Salt Lake City, DC, Austin) src/data/market-engine.ts — Generic engine generates neighborhoods, permits, time series, and scores for any market All explorer components now accept neighborhoods as props instead of importing Austin-only data Market selector with ?market= URL param support