fix(headless): 解决数据集维度数据类型映射空指针异常

- 添加对 dataTypeMap 的 containsKey 检查避免空指针异常
- 修复维度数据类型映射逻辑中的潜在运行时错误
- 确保在模型ID不存在时跳过数据类型映射操作

headless/server/src/main/java/com/tencent/supersonic/headless/server/utils/DataSetSchemaBuilder.java

@@ -123,8 +123,10 @@ public class DataSetSchemaBuilder {
                 dimToAdd.getExtInfo().put(DimensionConstants.DIMENSION_DATA_TYPE,
                         dim.getDataType());
             } else {
-                dimToAdd.getExtInfo().put(DimensionConstants.DIMENSION_DATA_TYPE,
-                        dataTypeMap.get(dim.getModelId()).get(dim.getBizName()));
+                if (dataTypeMap.containsKey(dim.getModelId())) {
+                    dimToAdd.getExtInfo().put(DimensionConstants.DIMENSION_DATA_TYPE,
+                            dataTypeMap.get(dim.getModelId()).get(dim.getBizName()));
+                }
             }
             if (dim.isTimeDimension()) {
                 String timeFormat =