fix(前端)：进度环方向 + 按钮颜色 + 删除确认 + 移除 console.log

- StartTask.vue：progress 计算改为 (total-current)/total*100，进度环从
  满到空递减（正确方向）
- ReviewDetail/ReviewRecall/MindMapViewer：type="primary" 全部改为
  type="success"，统一绿白主题
- Study.vue：删除任务增加 ElMessageBox.confirm 确认
- request.ts：移除全部 console.log

src/components/ReviewDetail.vue

@@ -295,7 +295,7 @@ watch(
         />
         <div class="edit-actions">
           <el-button @click="cancelEdit">取消</el-button>
-          <el-button type="primary" :loading="saving" @click="saveEdit">保存</el-button>
+          <el-button type="success" :loading="saving" @click="saveEdit">保存</el-button>
         </div>
       </div>
       <!-- 只读模式 -->
@@ -328,7 +328,7 @@ watch(
             >
               <el-button type="success" :loading="mindMapUploading">上传导图文件</el-button>
             </el-upload>
-            <el-button type="primary" size="small" @click="router.push(`/review/recall/${taskNum}`)">
+            <el-button type="success" size="small" @click="router.push(`/review/recall/${taskNum}`)">
               回忆复习
             </el-button>
             <el-tag v-if="mindMap?.fileFormat" size="small" effect="plain">

src/components/ReviewRecall.vue

@@ -328,7 +328,7 @@ onMounted(() => {
       <div class="panel-header">
         <h3>🧠 你的回忆</h3>
         <div class="panel-actions">
-          <el-button type="primary" :loading="comparing" @click="handleRecallCompare">
+          <el-button type="success" :loading="comparing" @click="handleRecallCompare">
             提交对比
           </el-button>
           <el-button v-if="hasCompared" @click="resetRecall">
@@ -389,7 +389,7 @@ onMounted(() => {
 
       <div v-if="!standard" class="empty-state">
         <el-empty description="暂无标准思维导图" :image-size="64">
-          <el-button type="primary" :loading="loading" @click="loadData">
+          <el-button type="success" :loading="loading" @click="loadData">
             生成
           </el-button>
         </el-empty>
@@ -400,7 +400,7 @@ onMounted(() => {
         <MindMapViewer ref="editViewer" :tree="standardTree" :editable="true" height="60vh" />
         <div class="edit-actions">
           <el-button @click="cancelStandardEdit">取消</el-button>
-          <el-button type="primary" :loading="savingStandard" @click="saveStandardEditFromViewer">
+          <el-button type="success" :loading="savingStandard" @click="saveStandardEditFromViewer">
             保存更新
           </el-button>
         </div>

src/components/StartTask.vue

@@ -81,7 +81,8 @@ const breakAudio = new Audio('/resource/notification.mp3');
 
 const progress = computed(() => {
   const total = isBreak.value ? 5 * 60 : 25 * 60;
-  return ((timerMinutes.value * 60 + timerSeconds.value) / total) * 100;
+  const current = timerMinutes.value * 60 + timerSeconds.value;
+  return ((total - current) / total) * 100;
 });
 const nowTimestamp = ref(Date.now());
 

src/components/Study.vue

@@ -2,7 +2,7 @@
 import { computed, onMounted, ref, watch } from "vue";
 import request from "@/utils/request";
 import router from "@/router";
-import { ElMessage } from "element-plus";
+import { ElMessage, ElMessageBox } from "element-plus";
 import { getReviewTaskStatsByTask } from "@/api/review";
 import {
   getPriorityWeights,
@@ -185,6 +185,15 @@ const removeTask = async () => {
     return;
   }
   const target = selectedTask.value;
+  try {
+    await ElMessageBox.confirm(`确定删除任务「${target.title}」？关联的学习会话、学习报告、应用场景等数据将被一并删除。`, "确认删除", {
+      confirmButtonText: "确定删除",
+      cancelButtonText: "取消",
+      type: "warning",
+    });
+  } catch {
+    return; // 用户取消
+  }
   const res = await request.del(`/tasks/${target.taskId}`, {});
   if (res.code === 200) {
     ElMessage.success(`任务 ${target.title} 删除成功`);