feat(cartesia): make pause_frame_processing configurable in CartesiaTTSService

Add pause_frame_processing parameter to CartesiaTTSService constructor
to allow users to disable frame processing pausing during TTS generation.

This is useful for use cases where text aggregation is disabled and
users want to send text directly to the TTS service without pausing
incoming frame processing.

src/pipecat/services/cartesia/tts.py

@@ -234,6 +234,7 @@ class CartesiaTTSService(AudioContextWordTTSService):
         params: Optional[InputParams] = None,
         text_aggregator: Optional[BaseTextAggregator] = None,
         aggregate_sentences: Optional[bool] = True,
+        pause_frame_processing: Optional[bool] = True,
         **kwargs,
     ):
         """Initialize the Cartesia TTS service.
@@ -254,6 +255,7 @@ class CartesiaTTSService(AudioContextWordTTSService):
                     Use an LLMTextProcessor before the TTSService for custom text aggregation.
 
             aggregate_sentences: Whether to aggregate sentences within the TTSService.
+            pause_frame_processing: Whether to pause processing frames while receiving audio.
             **kwargs: Additional arguments passed to the parent service.
         """
         # Aggregating sentences still gives cleaner-sounding results and fewer
@@ -269,7 +271,7 @@ class CartesiaTTSService(AudioContextWordTTSService):
         super().__init__(
             aggregate_sentences=aggregate_sentences,
             push_text_frames=False,
-            pause_frame_processing=True,
+            pause_frame_processing=pause_frame_processing,
             sample_rate=sample_rate,
             text_aggregator=text_aggregator,
             **kwargs,