Add APIs about max speech duration in VAD for various programming languages (#1349)

dart-api-examples/vad-with-non-streaming-asr/bin/paraformer.dart

@@ -32,6 +32,7 @@ void main(List<String> arguments) async {
     model: sileroVad,
     minSilenceDuration: 0.25,
     minSpeechDuration: 0.5,
+    maxSpeechDuration: 5.0,
   );
 
   final vadConfig = sherpa_onnx.VadModelConfig(

dart-api-examples/vad-with-non-streaming-asr/bin/sense-voice-2.dart

@@ -38,6 +38,7 @@ void main(List<String> arguments) async {
     model: sileroVad,
     minSilenceDuration: 0.25,
     minSpeechDuration: 0.5,
+    maxSpeechDuration: 5.0,
   );
 
   final vadConfig = sherpa_onnx.VadModelConfig(

dart-api-examples/vad-with-non-streaming-asr/bin/sense-voice.dart

@@ -37,6 +37,7 @@ void main(List<String> arguments) async {
     model: sileroVad,
     minSilenceDuration: 0.25,
     minSpeechDuration: 0.5,
+    maxSpeechDuration: 5.0,
   );
 
   final vadConfig = sherpa_onnx.VadModelConfig(

dart-api-examples/vad-with-non-streaming-asr/bin/telespeech-ctc.dart

@@ -33,6 +33,7 @@ void main(List<String> arguments) async {
     model: sileroVad,
     minSilenceDuration: 0.25,
     minSpeechDuration: 0.5,
+    maxSpeechDuration: 5.0,
   );
 
   final vadConfig = sherpa_onnx.VadModelConfig(

dart-api-examples/vad-with-non-streaming-asr/bin/whisper.dart

@@ -34,6 +34,7 @@ void main(List<String> arguments) async {
     model: sileroVad,
     minSilenceDuration: 0.25,
     minSpeechDuration: 0.5,
+    maxSpeechDuration: 5.0,
   );
 
   final vadConfig = sherpa_onnx.VadModelConfig(

dart-api-examples/vad-with-non-streaming-asr/bin/zipformer-transducer.dart

@@ -37,6 +37,7 @@ void main(List<String> arguments) async {
     model: sileroVad,
     minSilenceDuration: 0.25,
     minSpeechDuration: 0.5,
+    maxSpeechDuration: 5.0,
   );
 
   final vadConfig = sherpa_onnx.VadModelConfig(