When no mesh config exists (fresh install), scan for serial devices at /dev/ttyUSB* and /dev/ttyACM*. If a radio is found, auto-enable mesh and save the config so subsequent boots connect immediately. Previously, mesh defaulted to disabled and the radio was never probed unless the user manually created a mesh-config.json file. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>