Update SpeechmaticsSTTService to use the python voice SDK

changelog/3225.changed.md

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+- Updated `SpeechmaticsSTTService` to use new Python Voice SDK with improved VAD,
+  Smart Turn capabilities, and brings dramatic improvements to latency without
+  any impact on accuracy. Use the `turn_detection_mode` parameter to control the
+  endpointing of speech, with `TurnDetectionMode.EXTERNAL` (default),
+  `TurnDetectionMode.ADAPTIVE`, or `TurnDetectionMode.SMART_TURN`.
+  ```python
+    stt = SpeechmaticsSTTService(
+        api_key=os.getenv("SPEECHMATICS_API_KEY"),
+        params=SpeechmaticsSTTService.InputParams(
+            language=Language.EN,
+            turn_detection_mode=SpeechmaticsSTTService.TurnDetectionMode.ADAPTIVE,
+            speaker_active_format="<{speaker_id}>{text}</{speaker_id}>",
+        ),
+    )
+  ```

changelog/3225.deprecated.md

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+- For `SpeechmaticsSTTService`, the `end_of_utterance_mode` parameter is deprecated.
+  Use the new `turn_detection_mode` parameter instead, with `TurnDetectionMode.EXTERNAL`,
+  `TurnDetectionMode.ADAPTIVE`, or `TurnDetectionMode.SMART_TURN`. The `enable_vad`
+  parameter is also deprecated and is inferred from the `turn_detection_mode`.