fix: 预算操作列一致性 — 所有行都显示删除按钮(无记录时提示'暂无预算记录')

frontend/src/views/BudgetManagement.vue

@@ -69,7 +69,7 @@
             <template #default="{ row }">
               <el-button v-if="!batchEditMode && !row._editing" size="small" @click="startEdit(row)">编辑</el-button>
               <template v-else-if="!batchEditMode"><el-button size="small" type="primary" @click="saveEdit(row)" :loading="row._saving">保存</el-button><el-button size="small" @click="cancelEdit(row)">取消</el-button></template>
-              <el-button v-if="!batchEditMode && row.id" size="small" type="danger" plain @click="doDelete(row)">删除</el-button>
+              <el-button v-if="!batchEditMode" size="small" type="danger" plain @click="row.id ? doDelete(row) : ElMessage.info('该KPI暂无预算记录，无需删除')">删除</el-button>
             </template>
           </el-table-column>
         </el-table>