fix(types): change Content field type in MessageLog to interface{} for improved flexibility

apis/types.api

@@ -540,7 +540,7 @@ type (
 		Platform  string      `json:"platform"`
 		To        string      `json:"to"`
 		Subject   string      `json:"subject"`
-		Content   map[string]interface{} `json:"content"`
+		Content   interface{} `json:"content"`
 		Status    uint8       `json:"status"`
 		CreatedAt int64       `json:"created_at"`
 	}

internal/types/types.go

@@ -1023,7 +1023,7 @@ type MessageLog struct {
 	Platform  string      `json:"platform"`
 	To        string      `json:"to"`
 	Subject   string      `json:"subject"`
-	Content   map[string]interface{} `json:"content"`
+	Content   interface{} `json:"content"`
 	Status    uint8       `json:"status"`
 	CreatedAt int64       `json:"created_at"`
 }