Add debug logging to KrispVivaTurn analyze_end_of_turn and update example

Move speech detection tracking outside the per-frame loop in append_audio
since is_speech applies to the whole buffer. Add debug log in
analyze_end_of_turn to show state and probability at decision time. Update
the Krisp VIVA example to use Cartesia TTS and turn analyzer strategy.

examples/foundational/07p-interruptible-krisp-viva.py

@@ -41,12 +41,14 @@ from pipecat.processors.aggregators.llm_response_universal import (
 )
 from pipecat.runner.types import RunnerArguments
 from pipecat.runner.utils import create_transport
+from pipecat.services.cartesia.tts import CartesiaTTSService
 from pipecat.services.deepgram.stt import DeepgramSTTService
-from pipecat.services.deepgram.tts import DeepgramTTSService
 from pipecat.services.openai.llm import OpenAILLMService
 from pipecat.transports.base_transport import BaseTransport, TransportParams
 from pipecat.transports.daily.transport import DailyParams
 from pipecat.transports.websocket.fastapi import FastAPIWebsocketParams
+from pipecat.turns.user_stop import TurnAnalyzerUserTurnStopStrategy
+from pipecat.turns.user_turn_strategies import UserTurnStrategies
 
 load_dotenv(override=True)
 
@@ -76,7 +78,9 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
 
     stt = DeepgramSTTService(api_key=os.getenv("DEEPGRAM_API_KEY"))
 
-    tts = DeepgramTTSService(api_key=os.getenv("DEEPGRAM_API_KEY"), voice="aura-helios-en")
+    tts = CartesiaTTSService(
+        api_key=os.getenv("CARTESIA_API_KEY"), voice_id="71a7ad14-091c-4e8e-a314-022ece01c121"
+    )
 
     llm = OpenAILLMService(api_key=os.getenv("OPENAI_API_KEY"))