Embedded Agent Toolkit 0.15.0
Adds observation-only hardware-test contract stages for baud list, BLEA adapter doctor, and embedded-debugger probe listing. Contracts preserve component-native JSON evidence, require the matching board transport binding, classify BLE doctor as a bounded scan, and reject serial-open, BLE-connect, debug-attach, or target-control effects. Includes an ESP32-S3 discovery baseline example and expanded offline evaluation tests.