Every tool now returns a structured BaseModel instead of dict[str, Any], giving callers attribute access, IDE autocomplete, and schema validation. Adds ~30 model classes to models.py and updates all test assertions.
New mixins: - connectivity.py: adb_connect, adb_disconnect, adb_tcpip, adb_pair, device_properties (batch getprop) - settings.py: settings_get/put, wifi/bluetooth/airplane toggles, screen_brightness, screen_timeout, notification_list, clipboard_get, media_control Also fixes clipboard_set false-positive on devices where cmd clipboard returns exit 0 but has no implementation.
