(0.x) fix decoder: if no data was pushed, close the output channel (#1881)

Author: jayeshp19

.changeset/long-bikes-explain.md

@@ -0,0 +1,5 @@
+---
+"livekit-agents": patch
+---
+
+fix decoder: if no data was pushed, close the output channel

livekit-agents/livekit/agents/utils/codecs/decoder.py

@@ -131,6 +131,9 @@ def push(self, chunk: bytes):
 
     def end_input(self):
         self._input_buf.end_input()
+        if not self._started:
+            # if no data was pushed, close the output channel
+            self._output_ch.close()
 
     def _decode_loop(self):
         container: av.container.InputContainer | None = None