fix(media): 资源交付 - 按内容识别上传类型并统一重试与附件交付 (#678)

Co-authored-by: ddcat666 <26564566+ddcat666@users.noreply.github.com>

backend/internal/handler/resource_delivery.go

@@ -3,6 +3,7 @@ package handler
 import (
 	"fmt"
 	"io"
+	"mime"
 	"net/http"
 	"strings"
 
@@ -69,6 +70,12 @@ func serveResourceDelivery(c *gin.Context, delivery *service.ResourceDelivery, c
 		c.Header("Content-Disposition", disposition)
 	}
 	resource := stream.Resource
+	if !assets.InlineMediaType(resource.MimeType) {
+		if dispositionType, _, _ := mime.ParseMediaType(disposition); dispositionType != "attachment" {
+			c.Header("Content-Disposition", "attachment")
+		}
+		c.Header("Content-Security-Policy", "sandbox; default-src 'none'")
+	}
 	mimeType := resource.MimeType
 	if mimeType == "" {
 		mimeType = "application/octet-stream"