fix(home): 重绘二级筛选三线图标

lib/pages/home/widgets/home_grid_header.dart

@@ -342,10 +342,12 @@ class HomeGridHeader extends StatelessWidget {
                   child: Center(
                     child: SizedBox.square(
                       dimension: AppDimens.homeSecondaryFilterVisualSize,
-                      child: const Icon(
-                        Icons.filter_list_rounded,
-                        color: AppColors.textTertiary,
-                        size: AppDimens.homeSecondaryFilterIcon,
+                      child: const Center(
+                        child: CustomPaint(
+                          key: Key('home-secondary-filter-icon'),
+                          size: Size.square(AppDimens.homeSecondaryFilterIcon),
+                          painter: _ThreeLineFilterPainter(),
+                        ),
                       ),
                     ),
                   ),
@@ -395,3 +397,26 @@ class HomeGridHeader extends StatelessWidget {
     );
   }
 }
+
+class _ThreeLineFilterPainter extends CustomPainter {
+  const _ThreeLineFilterPainter();
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    final paint = Paint()
+      ..color = AppColors.textFilterIcon
+      ..strokeWidth = AppDimens.homeSecondaryFilterStroke
+      ..strokeCap = StrokeCap.butt;
+    final positions = [
+      size.height * 0.25,
+      size.height * 0.5,
+      size.height * 0.75,
+    ];
+    for (final y in positions) {
+      canvas.drawLine(Offset(0, y), Offset(size.width, y), paint);
+    }
+  }
+
+  @override
+  bool shouldRepaint(_ThreeLineFilterPainter oldDelegate) => false;
+}