Add option to disable network connectivity check when starting playback

[drygdryg]

I'm using your app to listen to audio via Bluetooth headphones connected to my smartphone, since I don't have a Bluetooth dongle for PC and can't connect headphones directly. To expose Pulseaudio TCP socket from PC to phone, I connect my phone using USB and use 'adb reverse`:

pactl load-module module-simple-protocol-tcp source=$audio_source record=true port=1234
adb reverse tcp:54321 tcp:1234

And then on the phone in SimpleProtocolPlayer I use 127.0.0.1:54321. But when the phone is not connected via Wi-Fi, I can't start playback, the app displays a toast notification with the error "No network connectivity." Could you add a checkbox to disable network connectivity check or completely remove it?

https://github.com/kaytat/SimpleProtocolPlayer/blob/8345ab801fc112fd8b246c55b8550a9bfabba69e/src/main/java/com/kaytat/simpleprotocolplayer/MainActivity.java#L373C13-L377

And thank you for the useful app!