feat: 出库/借库记录记录并展示库位快照（DB加列+后端写入+记录页展示）

inventory-web/src/views/transaction/records.vue

@@ -60,6 +60,12 @@
                   <el-tag v-else type="success">0</el-tag>
                 </template>
               </el-table-column>
+              <el-table-column prop="location" label="借出库位" min-width="120">
+                <template #default="{row}">
+                  <span v-if="row.location">{{ row.location }}</span>
+                  <span v-else style="color:#ccc">-</span>
+                </template>
+              </el-table-column>
               <el-table-column prop="return_location" label="归还库位" min-width="120">
                 <template #default="{row}">
                   <span v-if="row.return_location">{{ row.return_location }}</span>