增强预览机制

bin/router.dart

@@ -179,7 +179,15 @@ Future<Response> _getPhotoPreviewHandler(Request req) async {
     return Response.notFound('Photo not found');
   }
 
-  final file = await vips.generatePreview(photo.filePath);
+  // 从查询参数获取宽度和高度
+  final w = int.tryParse(req.url.queryParameters['w'] ?? '');
+  final h = int.tryParse(req.url.queryParameters['h'] ?? '');
+
+  final file = await vips.generatePreview(
+    photo.filePath,
+    w: w,
+    h: h,
+  );
 
   if (!await file.exists()) {
     return Response.notFound('File not found');
@@ -206,7 +214,7 @@ Future<Response> _getPhotoPreviewHandler(Request req) async {
   return Response.ok(
     streamController.stream,
     headers: {
-      'Content-Type': photo.mimeType,
+      'Content-Type': 'image/webp',
       'Content-Length': file.statSync().size.toString(),
     },
   );