feat: Improve embedding request handling and support across channels

- Update EmbeddingRequest DTO to support more flexible input types
- Add input parsing method to handle various input formats
- Implement ConvertEmbeddingRequest for multiple channel adaptors
- Remove relayMode parameter from EmbeddingHelper
- Add input validation for embedding requests
- Simplify embedding request conversion for different channels

dto/embedding.go

@@ -12,8 +12,35 @@ type EmbeddingOptions struct {
 }
 
 type EmbeddingRequest struct {
-	Model string   `json:"model"`
-	Input []string `json:"input"`
+	Model            string   `json:"model"`
+	Input            any      `json:"input"`
+	EncodingFormat   string   `json:"encoding_format,omitempty"`
+	Dimensions       int      `json:"dimensions,omitempty"`
+	User             string   `json:"user,omitempty"`
+	Seed             float64  `json:"seed,omitempty"`
+	Temperature      *float64 `json:"temperature,omitempty"`
+	TopP             float64  `json:"top_p,omitempty"`
+	FrequencyPenalty float64  `json:"frequency_penalty,omitempty"`
+	PresencePenalty  float64  `json:"presence_penalty,omitempty"`
+}
+
+func (r EmbeddingRequest) ParseInput() []string {
+	if r.Input == nil {
+		return nil
+	}
+	var input []string
+	switch r.Input.(type) {
+	case string:
+		input = []string{r.Input.(string)}
+	case []any:
+		input = make([]string, 0, len(r.Input.([]any)))
+		for _, item := range r.Input.([]any) {
+			if str, ok := item.(string); ok {
+				input = append(input, str)
+			}
+		}
+	}
+	return input
 }
 
 type EmbeddingResponseItem struct {
@@ -23,8 +50,8 @@ type EmbeddingResponseItem struct {
 }
 
 type EmbeddingResponse struct {
-	Object string                        `json:"object"`
+	Object string                  `json:"object"`
 	Data   []EmbeddingResponseItem `json:"data"`
-	Model  string                        `json:"model"`
+	Model  string                  `json:"model"`
 	Usage  `json:"usage"`
-}
+}