feat(purchase): 商家链接改为每行独立

- 明细表新增「商家链接」列，每行独立输入
- 移除公共区商家链接，公共信息区只保留审批人
- 提交时每行携带自己的 supplier_link

inventory-web/src/views/purchase/index.vue

@@ -144,6 +144,11 @@
                 </el-select>
               </template>
             </el-table-column>
+            <el-table-column label="商家链接" min-width="160">
+              <template #default="{ row }">
+                <el-input v-model="row.supplier_link" placeholder="https://" clearable />
+              </template>
+            </el-table-column>
             <el-table-column label="备注" min-width="150">
               <template #default="{ row }">
                 <el-input v-model="row.remark" type="textarea" :rows="1" placeholder="行备注" resize="none" />
@@ -177,7 +182,7 @@
           </el-table>
         </div>
 
-        <!-- ── 公共信息：审批人 / 链接 ── -->
+        <!-- ── 公共信息：审批人 ── -->
         <div class="form-section">
           <div class="section-title"><span>公共信息</span></div>
           <el-row :gutter="16">
@@ -188,11 +193,6 @@
                 </el-select>
               </el-form-item>
             </el-col>
-            <el-col :span="12">
-              <el-form-item label="商家链接">
-                <el-input v-model="form.supplier_link" placeholder="https://" clearable />
-              </el-form-item>
-            </el-col>
           </el-row>
         </div>
 
@@ -347,7 +347,6 @@ const vLoadmore = {
 // 表单（公共字段）
 const form = ref({
   approver_id: undefined as number | undefined,
-  supplier_link: '',
   remark: ''
 })
 
@@ -363,6 +362,7 @@ interface FormItemRow {
   total_price: number | undefined
   tax_rate: number
   totalPriceManuallyEdited: boolean
+  supplier_link: string
   remark: string
   images: string[]
   fileList: any[]
@@ -381,6 +381,7 @@ const createEmptyFormItem = (): FormItemRow => ({
   total_price: undefined,
   tax_rate: 0,
   totalPriceManuallyEdited: false,
+  supplier_link: '',
   remark: '',
   images: [],
   fileList: []
@@ -464,7 +465,6 @@ const openCreateDialog = (prefill?: { materialId?: number; name?: string; spec?:
   dialogTitle.value = '新建采购申请'
   form.value = {
     approver_id: undefined,
-    supplier_link: '',
     remark: ''
   }
 
@@ -773,7 +773,8 @@ const submitForm = async () => {
         total_price: row.total_price,
         tax_rate: row.tax_rate,
         approver_id: form.value.approver_id,
-        supplier_link: form.value.supplier_link,
+        // ★ 商家链接每行独立
+        supplier_link: row.supplier_link || '',
         // 行备注优先；若空则用公共备注
         remark: row.remark || form.value.remark,
         // ★ 每行必填照片