feat(mybatis): 扩展LambdaQueryWrapperX查询功能

- 添加Consumer函数式接口支持复杂条件构建
- 实现exists和notExists子查询方法
- 实现and、or、nested、not条件组合方法
- 所有新增方法均支持链式调用返回自身实例
- 统一方法签名确保与父类QueryWrapper兼容性

yudao-framework/yudao-spring-boot-starter-mybatis/src/main/java/cn/iocoder/yudao/framework/mybatis/core/query/LambdaQueryWrapperX.java

@@ -9,6 +9,7 @@ import org.springframework.util.StringUtils;
 
 import java.time.LocalDateTime;
 import java.util.Collection;
+import java.util.function.Consumer;
 
 /**
  * 拓展 MyBatis Plus QueryWrapper 类，主要增加如下功能：
@@ -158,4 +159,40 @@ public class LambdaQueryWrapperX<T> extends LambdaQueryWrapper<T> {
         return this;
     }
 
+    @Override
+    public LambdaQueryWrapperX<T> exists(boolean condition, String existsSql, Object... values) {
+        super.exists(condition, existsSql, values);
+        return this;
+    }
+
+    @Override
+    public LambdaQueryWrapperX<T> notExists(boolean condition, String existsSql, Object... values) {
+        super.notExists(condition, existsSql, values);
+        return this;
+    }
+
+    @Override
+    public LambdaQueryWrapperX<T> and(boolean condition, Consumer<LambdaQueryWrapper<T>> consumer) {
+        super.and(condition,consumer);
+        return this;
+    }
+
+    @Override
+    public LambdaQueryWrapperX<T> or(boolean condition, Consumer<LambdaQueryWrapper<T>> consumer) {
+        super.or(condition, consumer);
+        return this;
+    }
+
+    @Override
+    public LambdaQueryWrapperX<T> nested(boolean condition, Consumer<LambdaQueryWrapper<T>> consumer) {
+        super.nested(condition, consumer);
+        return this;
+    }
+
+    @Override
+    public LambdaQueryWrapperX<T> not(boolean condition, Consumer<LambdaQueryWrapper<T>> consumer) {
+        super.not(condition, consumer);
+        return this;
+    }
+
 }