fix(ui): 修复上下文模式对比开关无法切换的问题

- 将事件监听从 @update:is-compare-mode 改为 @compare-toggle
- TestControlBar 组件只 emit compare-toggle 事件，之前监听错误导致开关失效
- 修改 handleCompareModeToggle 为 handleCompareToggle 并使用状态取反

Author: linshenkx

packages/ui/src/components/context-mode/ContextUserTestPanel.vue

@@ -146,7 +146,7 @@
                 :model-label="t('test.model')"
                 :show-compare-toggle="enableCompareMode"
                 :is-compare-mode="isCompareMode"
-                @update:is-compare-mode="handleCompareModeToggle"
+                @compare-toggle="handleCompareToggle"
                 :primary-action-text="primaryActionText"
                 :primary-action-disabled="primaryActionDisabled"
                 :primary-action-loading="isTestRunning"
@@ -342,8 +342,8 @@ const emit = defineEmits<{
 }>();
 
 // 处理对比模式切换
-const handleCompareModeToggle = (value: boolean) => {
-    emit("update:isCompareMode", value);
+const handleCompareToggle = () => {
+    emit("update:isCompareMode", !props.isCompareMode);
     emit("compare-toggle");
     recordUpdate();
 };

packages/ui/src/components/context-mode/ConversationTestPanel.vue

@@ -146,7 +146,7 @@
                 :model-label="t('test.model')"
                 :show-compare-toggle="enableCompareMode"
                 :is-compare-mode="isCompareMode"
-                @update:is-compare-mode="handleCompareModeToggle"
+                @compare-toggle="handleCompareToggle"
                 :primary-action-text="primaryActionText"
                 :primary-action-disabled="primaryActionDisabled"
                 :primary-action-loading="isTestRunning"
@@ -408,8 +408,8 @@ const originalToolCalls = ref<ToolCallResult[]>([]);
 const optimizedToolCalls = ref<ToolCallResult[]>([]);
 
 // 🆕 处理对比模式切换
-const handleCompareModeToggle = (value: boolean) => {
-    emit("update:isCompareMode", value);
+const handleCompareToggle = () => {
+    emit("update:isCompareMode", !props.isCompareMode);
     emit("compare-toggle");
     recordUpdate();
 };