Fix Bug #273: 门诊医生站-》医嘱TAB页面：修改用药天数字段的值，总量字段的值未自动通过公式换算

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

openhis-ui-vue3/src/views/doctorstation/components/prescription/prescriptionlist.vue

@@ -313,6 +313,7 @@
                       data-prop="dispensePerDuration">
                       <el-input-number v-model="scope.row.dispensePerDuration" style="width: 80px" :min="1"
                         controls-position="right" :controls="false" :ref="(el) => (inputRefs.dispensePerDuration = el)"
+                        @change="calculateTotalAmount(scope.row, scope.$index)"
                         @keyup.enter.prevent="
                           handleEnter('dispensePerDuration', scope.row, scope.$index)
                           ">