实现缩放功能：增加缩放功能检索和设置方法，更新UI以支持缩放调整，增强缩放比例的状态管理。

lib/features/recording/widgets/widget_record_header.dart

@@ -170,7 +170,7 @@ class _HeaderPasteActions extends StatelessWidget {
     return Row(
       mainAxisAlignment: MainAxisAlignment.end,
       children: [
-        // _HeaderActionButton(label: 'mock', onPressed: onMockCopy),
+        _HeaderActionButton(label: 'mock', onPressed: onMockCopy),
         _HeaderActionButton(
           label: '粘贴选手信息',
           onPressed: () => onPasteEventInfo(),

lib/features/recording/widgets/widget_recording_hud.dart

@@ -21,11 +21,15 @@ class RecordingHudWidget extends StatelessWidget {
     required this.isTouchLocked,
     this.showClipboardHint = false,
     this.clipboardAddress = '',
+    required this.zoomRatio,
+    required this.minZoomRatio,
+    required this.maxZoomRatio,
     required this.onStart,
     required this.onStop,
     required this.onOpenDnd,
     required this.onOpenBattery,
     required this.onToggleTouchLock,
+    required this.onZoomSelected,
   });
 
   final String? errorMessage;
@@ -38,16 +42,21 @@ class RecordingHudWidget extends StatelessWidget {
   final bool isTouchLocked;
   final bool showClipboardHint;
   final String clipboardAddress;
+  final double zoomRatio;
+  final double minZoomRatio;
+  final double maxZoomRatio;
   final Future<void> Function() onStart;
   final Future<void> Function() onStop;
   final VoidCallback onOpenDnd;
   final VoidCallback onOpenBattery;
   final VoidCallback onToggleTouchLock;
+  final ValueChanged<double> onZoomSelected;
 
   static double get _recordButtonSize => 70.r;
   static double get _recordButtonBottom => 63.r;
   static double get _overlayInfoLeft => 13.r;
   static double get _overlayInfoBottom => 10.r;
+  static const List<double> _zoomPresets = [1.0, 2.0, 3.0];
 
   @override
   Widget build(BuildContext context) {
@@ -133,6 +142,17 @@ class RecordingHudWidget extends StatelessWidget {
               ),
             ),
           ),
+        Positioned(
+          right: 16.r,
+          bottom: _recordButtonBottom + _recordButtonSize + 14.h,
+          child: _ZoomPresetControl(
+            zoomRatio: zoomRatio,
+            minZoomRatio: minZoomRatio,
+            maxZoomRatio: maxZoomRatio,
+            presets: _zoomPresets,
+            onSelected: onZoomSelected,
+          ),
+        ),
         Positioned(
           left: 0,
           right: 0,
@@ -171,3 +191,94 @@ class RecordingHudWidget extends StatelessWidget {
     );
   }
 }
+
+class _ZoomPresetControl extends StatelessWidget {
+  const _ZoomPresetControl({
+    required this.zoomRatio,
+    required this.minZoomRatio,
+    required this.maxZoomRatio,
+    required this.presets,
+    required this.onSelected,
+  });
+
+  final double zoomRatio;
+  final double minZoomRatio;
+  final double maxZoomRatio;
+  final List<double> presets;
+  final ValueChanged<double> onSelected;
+
+  @override
+  Widget build(BuildContext context) {
+    final availablePresets = presets
+        .where((preset) => preset >= minZoomRatio && preset <= maxZoomRatio)
+        .toList(growable: false);
+
+    if (availablePresets.isEmpty) {
+      return const SizedBox.shrink();
+    }
+
+    return DecoratedBox(
+      decoration: BoxDecoration(
+        color: Colors.black.withValues(alpha: 0.46),
+        borderRadius: BorderRadius.circular(18.r),
+        border: Border.all(color: Colors.white.withValues(alpha: 0.18)),
+      ),
+      child: Padding(
+        padding: EdgeInsets.all(3.r),
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            for (final preset in availablePresets)
+              _ZoomPresetButton(
+                ratio: preset,
+                selected: (zoomRatio - preset).abs() < 0.05,
+                onSelected: onSelected,
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+class _ZoomPresetButton extends StatelessWidget {
+  const _ZoomPresetButton({
+    required this.ratio,
+    required this.selected,
+    required this.onSelected,
+  });
+
+  final double ratio;
+  final bool selected;
+  final ValueChanged<double> onSelected;
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: EdgeInsets.symmetric(horizontal: 1.r),
+      child: TextButton(
+        onPressed: selected ? null : () => onSelected(ratio),
+        style: TextButton.styleFrom(
+          minimumSize: Size(38.r, 32.r),
+          padding: EdgeInsets.zero,
+          tapTargetSize: MaterialTapTargetSize.shrinkWrap,
+          foregroundColor: selected ? Colors.black : Colors.white,
+          disabledForegroundColor: Colors.black,
+          backgroundColor: selected ? Colors.white : Colors.transparent,
+          disabledBackgroundColor: Colors.white,
+          shape: RoundedRectangleBorder(
+            borderRadius: BorderRadius.circular(15.r),
+          ),
+        ),
+        child: Text(
+          '${ratio.toStringAsFixed(0)}x',
+          style: TextStyle(
+            fontSize: 13.sp,
+            fontWeight: FontWeight.w700,
+            letterSpacing: 0,
+          ),
+        ),
+      ),
+    );
+  }
+}