Recover wearable connections after Bluetooth power cycles

[TobiasRoeddiger]

After phone Bluetooth is switched off and on, missing disconnect callbacks can leave a wearable marked connected and retain an Android GATT handle tied to the stopped Bluetooth service. Reconnect then fails or repeatedly times out.

Treat adapter power-off as a disconnect for each tracked device, release its native connection, and wait for cleanup before reconnecting. Late service discovery from an old connection cannot complete or remove a newer attempt.

Validation: four regression tests cover missing/duplicate disconnect events, both wearable-manager IDs, delayed native cleanup, and stale discovery completion; all 21 package tests and analysis pass. Reproduced the native dead-handle loop on Pixel 9a; the complete patch passed six power cycles (three without music, three with music). Both ears recovered within 10 seconds each time, and fresh IMU data returned without an app restart. Music trials used only IMU on both ears to isolate reconnect from the separately observed mixed-sensor throughput loss.

[github-actions]

Visit the preview URL for this PR (updated for commit 9d08da1):

https://open-earable-lib-web-example--pr153-codex-bluetooth-po-791sa9ea.web.app

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