feat: 细化差旅票据费用明细分类并自动计算出差补贴

将差旅费用明细拆分为火车票、机票、住宿票、乘车等细分类
型，根据票据字段自动生成行程/事由描述，结合规则引擎自
动计算出差补贴金额，前端适配费用明细编辑和差旅票据审
核交互，补充单元测试覆盖。

web/src/views/TravelRequestDetailView.vue

@@ -88,6 +88,46 @@
 
         <div class="detail-grid">
           <section class="detail-left">
+            <article class="detail-card panel">
+              <div class="detail-card-head">
+                <div>
+                  <h3>附加说明</h3>
+                  <p>用于说明本次出差或办事目的，例如去哪里、拜访谁、处理什么事项。</p>
+                </div>
+              </div>
+              <div v-if="canEditDetailNote" class="detail-note-editor">
+                <textarea
+                  v-model="detailNoteEditor"
+                  maxlength="500"
+                  placeholder="例如：去北京客户现场出差，拜访 XX 客户并处理项目验收事项"
+                  aria-label="附加说明"
+                ></textarea>
+                <div class="detail-note-editor-meta">
+                  <span>仅草稿待提交状态可编辑，提交后将作为明确说明展示。</span>
+                  <div class="detail-note-actions">
+                    <button
+                      v-if="detailNoteDirty"
+                      class="inline-action"
+                      type="button"
+                      :disabled="savingDetailNote"
+                      @click="resetDetailNote"
+                    >
+                      恢复
+                    </button>
+                    <button
+                      class="inline-action primary"
+                      type="button"
+                      :disabled="!detailNoteDirty || savingDetailNote"
+                      @click="saveDetailNote"
+                    >
+                      {{ savingDetailNote ? '保存中' : '保存说明' }}
+                    </button>
+                  </div>
+                </div>
+              </div>
+              <div v-else class="detail-note readonly">{{ detailNote }}</div>
+            </article>
+
             <article class="detail-card panel">
               <div class="detail-card-head">
                 <div>
@@ -129,7 +169,7 @@
                   </thead>
                   <tbody>
                     <template v-for="item in expenseItems" :key="item.id">
-                      <tr>
+                      <tr :class="{ 'system-generated-row': item.isSystemGenerated }">
                         <td class="expense-time col-time">
                           <template v-if="editingExpenseId === item.id">
                             <div class="cell-editor">
@@ -200,8 +240,8 @@
                           <template v-if="editingExpenseId === item.id">
                             <div class="cell-editor editor-stack">
                               <div class="attachment-action-group">
-                                <button
-                                  v-if="isEditableRequest && !item.invoiceId"
+                              <button
+                                  v-if="isEditableRequest && !item.invoiceId && !item.isSystemGenerated"
                                   class="icon-action upload"
                                   type="button"
                                   title="上传单据"
@@ -221,8 +261,8 @@
                                 >
                                   <i class="mdi mdi-eye-outline"></i>
                                 </button>
-                                <button
-                                  v-if="isEditableRequest && item.invoiceId"
+                              <button
+                                  v-if="isEditableRequest && item.invoiceId && !item.isSystemGenerated"
                                   class="icon-action danger"
                                   type="button"
                                   title="删除附件"
@@ -236,9 +276,13 @@
                             </div>
                           </template>
                           <template v-else>
-                            <div class="attachment-action-group">
+                            <div v-if="item.isSystemGenerated" class="system-attachment-note">
+                              <i class="mdi mdi-calculator-variant-outline"></i>
+                              <span>无需附件</span>
+                            </div>
+                            <div v-else class="attachment-action-group">
                               <button
-                                v-if="isEditableRequest && !item.invoiceId"
+                                v-if="isEditableRequest && !item.invoiceId && !item.isSystemGenerated"
                                 class="icon-action upload"
                                 type="button"
                                 title="上传单据"
@@ -259,7 +303,7 @@
                                 <i class="mdi mdi-eye-outline"></i>
                               </button>
                               <button
-                                v-if="isEditableRequest && item.invoiceId"
+                                v-if="isEditableRequest && item.invoiceId && !item.isSystemGenerated"
                                 class="icon-action danger"
                                 type="button"
                                 title="删除附件"
@@ -273,7 +317,11 @@
                           </template>
                         </td>
                         <td v-if="isEditableRequest" class="expense-action-cell col-action">
-                          <div v-if="editingExpenseId === item.id" class="row-action-group">
+                          <div v-if="item.isSystemGenerated" class="system-row-lock">
+                            <i class="mdi mdi-lock-outline"></i>
+                            <span>系统计算</span>
+                          </div>
+                          <div v-else-if="editingExpenseId === item.id" class="row-action-group">
                             <button
                               class="inline-action primary"
                               type="button"
@@ -328,6 +376,10 @@
                   </tbody>
                 </table>
               </div>
+              <div v-if="expenseItems.length" class="expense-total-under-table">
+                <span>金额合计</span>
+                <strong>{{ expenseTotal }}</strong>
+              </div>
             </article>
 
             <article v-if="isEditableRequest" class="detail-card panel validation-card">
@@ -339,39 +391,43 @@
                 <span :class="['validation-pill', aiAdvice.tone]">{{ aiAdvice.badge }}</span>
               </div>
               <p class="validation-summary">{{ aiAdvice.summary }}</p>
-              <div v-if="aiAdvice.riskCards.length" class="risk-advice-list">
-                <article
-                  v-for="card in aiAdvice.riskCards"
-                  :key="card.id"
-                  :class="['risk-advice-card', card.tone]"
+              <div v-if="aiAdvice.sections.length" class="validation-sections">
+                <section
+                  v-for="section in aiAdvice.sections"
+                  :key="section.kind"
+                  :class="['validation-section', `validation-section--${section.kind}`]"
                 >
-                  <div class="risk-advice-card-head">
-                    <span>{{ card.label }}</span>
-                    <strong>{{ card.title }}</strong>
+                  <h4 class="validation-section-title">{{ section.title }}</h4>
+                  <ul v-if="section.kind === 'completion'" class="validation-list">
+                    <li v-for="item in section.items" :key="item">{{ item }}</li>
+                  </ul>
+                  <div v-else class="risk-advice-list">
+                    <article
+                      v-for="card in section.items"
+                      :key="card.id"
+                      :class="['risk-advice-card', card.tone]"
+                    >
+                      <div class="risk-advice-card-head">
+                        <span>{{ card.label }}</span>
+                        <strong>{{ card.title }}</strong>
+                      </div>
+                      <p class="risk-advice-point">{{ card.risk }}</p>
+                      <div class="risk-advice-meta">
+                        <div>
+                          <span>规则依据</span>
+                          <ul>
+                            <li v-for="basis in card.ruleBasis" :key="basis">{{ basis }}</li>
+                          </ul>
+                        </div>
+                        <div>
+                          <span>修改建议</span>
+                          <p>{{ card.suggestion }}</p>
+                        </div>
+                      </div>
+                    </article>
                   </div>
-                  <p class="risk-advice-point">{{ card.risk }}</p>
-                  <div class="risk-advice-meta">
-                    <div>
-                      <span>规则依据</span>
-                      <ul>
-                        <li v-for="basis in card.ruleBasis" :key="basis">{{ basis }}</li>
-                      </ul>
-                    </div>
-                    <div>
-                      <span>修改建议</span>
-                      <p>{{ card.suggestion }}</p>
-                    </div>
-                  </div>
-                </article>
+                </section>
               </div>
-              <ul v-if="aiAdvice.items.length" class="validation-list">
-                <li v-for="item in aiAdvice.items" :key="item">{{ item }}</li>
-              </ul>
-            </article>
-
-            <article class="detail-card panel">
-              <h3>附加说明</h3>
-              <div class="detail-note">{{ detailNote }}</div>
             </article>
 
             <article v-if="showLeaderApprovalPanel" class="detail-card panel leader-approval-card">