refactor: formaliza formatos de áudio e alinhamento PCM

tests/test_voice_pipeline.py

@@ -1,5 +1,4 @@
 from voice_assistant.agent.adapter import StreamingAgentAdapter
-from voice_assistant.tts.adapter import TTSAdapter
 """
 Tests for the Voice Pipeline lifecycle orchestration.
 
@@ -850,9 +849,9 @@ async def test_stream_turn_response_produces_audio_before_agent_finishes():
             yield " Estou à disposição."
             self.finished = True
 
-    class StreamingTTS(TTSAdapter):
+    class StreamingTTS(MockTTSAdapter):
         async def synthesize(self, text):
-            yield text.encode("utf-8")
+            yield text.encode("utf-16-le")
 
     agent = StreamingAgent()
 
@@ -938,9 +937,9 @@ async def test_stream_turn_response_propagates_agent_failure():
             yield "Olá, como posso ajudar?"
             raise RuntimeError("Simulated OCI streaming failure.")
 
-    class StreamingTTS(TTSAdapter):
+    class StreamingTTS(MockTTSAdapter):
         async def synthesize(self, text):
-            yield text.encode("utf-8")
+            yield text.encode("utf-16-le")
 
     pipeline = VoicePipeline(
         session=SessionState(session_id="agent-failure-session"),
@@ -984,7 +983,7 @@ async def test_stream_turn_response_cancels_agent_on_tts_failure():
             finally:
                 self.cancelled.set()
 
-    class FailingTTS(TTSAdapter):
+    class FailingTTS(MockTTSAdapter):
         async def synthesize(self, text):
             raise RuntimeError("Simulated TTS failure.")
             yield b""  # Keep this method an async generator.
@@ -1036,7 +1035,7 @@ async def test_stream_turn_response_external_cancellation():
             finally:
                 self.closed.set()
 
-    class BlockingTTS(TTSAdapter):
+    class BlockingTTS(MockTTSAdapter):
         def __init__(self):
             self.started = asyncio.Event()
             self.closed = asyncio.Event()
@@ -1045,7 +1044,7 @@ async def test_stream_turn_response_external_cancellation():
             try:
                 self.started.set()
                 await asyncio.Event().wait()
-                yield b"audio"
+                yield b"audi"
             finally:
                 self.closed.set()