Load wrapper clients

Testing with:

```yaml
name: gpt-4o
pipeline:
 tts: voice-it-riccardo_fasol-x-low
 transcription: whisper-base-q5_1
 llm: llama-3.2-1b-instruct:q4_k_m
```

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

core/config/backend_config.go

@@ -81,7 +81,7 @@ type BackendConfig struct {
 type Pipeline struct {
 	TTS           string `yaml:"tts"`
 	LLM           string `yaml:"llm"`
-	Transcription string `yaml:"sst"`
+	Transcription string `yaml:"transcription"`
 }
 
 type File struct {

core/http/endpoints/openai/realtime.go

@@ -10,7 +10,9 @@ import (
 	"github.com/gofiber/websocket/v2"
 	"github.com/mudler/LocalAI/core/backend"
 	"github.com/mudler/LocalAI/core/config"
+	grpc "github.com/mudler/LocalAI/pkg/grpc"
 	model "github.com/mudler/LocalAI/pkg/model"
+
 	"github.com/rs/zerolog/log"
 )
 
@@ -111,13 +113,17 @@ type Model interface {
 }
 
 type wrappedModel struct {
-	TTS *config.BackendConfig
-	SST *config.BackendConfig
-	LLM *config.BackendConfig
+	TTSConfig           *config.BackendConfig
+	TranscriptionConfig *config.BackendConfig
+	LLMConfig           *config.BackendConfig
+	TTSClient           grpc.Backend
+	TranscriptionClient grpc.Backend
+	LLMClient           grpc.Backend
 }
 
 // returns and loads either a wrapped model or a model that support audio-to-audio
 func newModel(cl *config.BackendConfigLoader, ml *model.ModelLoader, appConfig *config.ApplicationConfig, modelName string) (Model, error) {
+
 	cfg, err := cl.LoadBackendConfigFileByName(modelName, ml.ModelPath)
 	if err != nil {
 		return nil, fmt.Errorf("failed to load backend config: %w", err)
@@ -134,6 +140,8 @@ func newModel(cl *config.BackendConfigLoader, ml *model.ModelLoader, appConfig *
 		return ml.BackendLoader(opts...)
 	}
 
+	log.Debug().Msg("Loading a wrapped model")
+
 	// Otherwise we want to return a wrapped model, which is a "virtual" model that re-uses other models to perform operations
 	cfgLLM, err := cl.LoadBackendConfigFileByName(cfg.Pipeline.LLM, ml.ModelPath)
 	if err != nil {
@@ -165,10 +173,31 @@ func newModel(cl *config.BackendConfigLoader, ml *model.ModelLoader, appConfig *
 		return nil, fmt.Errorf("failed to validate config: %w", err)
 	}
 
+	opts := backend.ModelOptions(*cfgTTS, appConfig)
+	ttsClient, err := ml.BackendLoader(opts...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load tts model: %w", err)
+	}
+
+	opts = backend.ModelOptions(*cfgSST, appConfig)
+	transcriptionClient, err := ml.BackendLoader(opts...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load SST model: %w", err)
+	}
+
+	opts = backend.ModelOptions(*cfgLLM, appConfig)
+	llmClient, err := ml.BackendLoader(opts...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load LLM model: %w", err)
+	}
+
 	return &wrappedModel{
-		TTS: cfgTTS,
-		SST: cfgSST,
-		LLM: cfgLLM,
+		TTSConfig:           cfgTTS,
+		TranscriptionConfig: cfgSST,
+		LLMConfig:           cfgLLM,
+		TTSClient:           ttsClient,
+		TranscriptionClient: transcriptionClient,
+		LLMClient:           llmClient,
 	}, nil
 }