Adopt Android CLI for launching emulators and updating dev skills

Investigate the official `android` CLI (announced Google I/O 2026) for scripting emulator launch/device management, and consider replacing current ad-hoc emulator scripts (CI and local dev skills, e.g. btrace-perfetto) with it for more reliable automation.

Start by reviewing the current emulator scripts used in CI and local development skills, including btrace-perfetto, then investigate the official android CLI's emulator launch and device-management capabilities. Done means documenting whether it can replace the ad-hoc automation and, if suitable, updating the affected scripts consistently.

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