The ALLOWED_SERIALS guard matched the adb transport serial, which over
WiFi is a rotating ip:port (changes on every wireless-debugging restart)
and over USB is the bare hardware serial. Pinning the transport serial
meant every port rotation broke the deploy until the profile was hand-edited.
Resolve the device's stable ro.serialno (getprop) after target resolution
and match that against ALLOWED_SERIALS instead. The transport serial still
drives adb/gradle/ANDROID_SERIAL; only the wrong-watch guard switches to the
stable identity, so it survives port rotation and is identical over WiFi/USB.
Also: 'devices' now prints 'transport -> ro.serialno' per device to make the
value for ALLOWED_SERIALS easy to read off. Help text and the example profile
are updated to the ro.serialno form.
closes#6
Adds the directory, gitignore rule, and checked-in template. Real profile
files (e.g. brummel-dev.sh) live alongside but are gitignored as they
contain plaintext api_keys.
refs #3
Brummel