Add a default noise floor. (#13)

(Turns out not) Pretty simple, if the average amplitude is under a certain value clear
out the buffer! The value I chose (.001) was an arbitrary value I got
from printf debugging. I was able to show that this worked pretty well
on the desktop session. Hopefully we'll add this to the settings page at
some point.

Once the app has been under that threshold for more than 200ms, we stop transmitting and send a terminator packet.

Reviewed-on: #13
Reviewed-by: restitux <restitux@ohea.xyz>

gui/src/lib.rs

@@ -114,14 +114,14 @@ pub async fn network_loop<R: imp::ImpRead, W: imp::ImpWrite>(
     {
         let send_chan = send_chan.clone();
         let mut sequence_num = 0;
-        audio.start_recording(move |opus_frame| {
+        audio.start_recording(move |opus_frame, is_terminator| {
             let _ =
                 send_chan.unbounded_send(ControlPacket::UDPTunnel(Box::new(VoicePacket::Audio {
                     _dst: std::marker::PhantomData,
                     target: 0,
                     session_id: (),
                     seq_num: sequence_num,
-                    payload: VoicePacketPayload::Opus(opus_frame.into(), false),
+                    payload: VoicePacketPayload::Opus(opus_frame.into(), is_terminator),
                     position_info: None,
                 })));
             sequence_num = sequence_num.wrapping_add(2);