Support extra languages in multi-lang kokoro tts (#2303)

scripts/dotnet/OfflineTtsKokoroModelConfig.cs

@@ -18,6 +18,7 @@ namespace SherpaOnnx
 
             DictDir = "";
             Lexicon = "";
+            Lang = "";
         }
         [MarshalAs(UnmanagedType.LPStr)]
         public string Model;
@@ -38,5 +39,8 @@ namespace SherpaOnnx
 
         [MarshalAs(UnmanagedType.LPStr)]
         public string Lexicon;
+
+        [MarshalAs(UnmanagedType.LPStr)]
+        public string Lang;
     }
 }

scripts/go/sherpa_onnx.go

@@ -857,6 +857,7 @@ type OfflineTtsKokoroModelConfig struct {
 	DataDir     string  // Path to espeak-ng-data directory
 	DictDir     string  // Path to dict directory
 	Lexicon     string  // Path to lexicon files
+	Lang        string  // Example: es for Spanish, fr-fr for French. Can be empty
 	LengthScale float32 // Please use 1.0 in general. Smaller -> Faster speech speed. Larger -> Slower speech speed
 }
 
@@ -1006,6 +1007,9 @@ func NewOfflineTts(config *OfflineTtsConfig) *OfflineTts {
 	c.model.kokoro.lexicon = C.CString(config.Model.Kokoro.Lexicon)
 	defer C.free(unsafe.Pointer(c.model.kokoro.lexicon))
 
+	c.model.kokoro.lang = C.CString(config.Model.Kokoro.Lang)
+	defer C.free(unsafe.Pointer(c.model.kokoro.lang))
+
 	c.model.kokoro.length_scale = C.float(config.Model.Kokoro.LengthScale)
 
 	c.model.num_threads = C.int(config.Model.NumThreads)