fix(forecast-form): 调整预测数量输入框的布局宽度

src/components/forecast-form/index.vue

@@ -125,7 +125,7 @@
             </el-col>
           </el-row>
           <el-row :gutter="20">
-            <el-col :span="24">
+            <el-col :span="12">
               <el-form-item label="预测数量" prop="forecastQuantity">
                 <div class="forecast-quantity-section">
                   <el-input-number