refactor: 减分从满分开始

src/components/marking/components/renderer/QuestionRenderer.vue

@@ -145,10 +145,28 @@ function undo() {
  */
 function handleQuickScore(value: number) {
   if (currentMarkingData.value) {
-    const currentScore = currentMarkingData.value.score === -1 ? 0 : currentMarkingData.value.score
+    // 减分模式：如果当前分数是-1（未打分），则从满分开始减
+    const currentScore =
+      currentMarkingData.value.score === -1
+        ? markingSettings.value.scoreMode === 'subtract'
+          ? props.question.fullScore
+          : 0
+        : currentMarkingData.value.score
+
+    // 检查边界
+    if (value > 0 && currentScore >= props.question.fullScore) {
+      return false
+    }
+    if (value < 0 && currentScore <= 0) {
+      return false
+    }
+
     const newScore = Math.max(0, Math.min(props.question.fullScore, currentScore + value))
     currentMarkingData.value.score = newScore
+    return true
   }
+
+  return false
 }
 
 // 问题卷对话框引用