docs 补充项目注释

ruoyi-common/ruoyi-common-mybatis/src/main/java/com/github/yulichang/injector/MPJSqlInjector.java

@@ -143,6 +143,12 @@ public class MPJSqlInjector extends DefaultSqlInjector {
         TableHelper.init(modelClass, supplier.get());
     }
 
+    /**
+     * 兼容旧版泛型解析逻辑，提取 Mapper 绑定的实体类型。
+     *
+     * @param mapperClass Mapper 类型
+     * @return Mapper 泛型中的实体类型，无法解析时返回 null
+     */
     @SuppressWarnings("IfStatementWithIdenticalBranches")
     protected Class<?> extractModelClassOld(Class<?> mapperClass) {
         Type[] types = mapperClass.getGenericInterfaces();

ruoyi-common/ruoyi-common-mybatis/src/main/java/org/dromara/common/mybatis/config/MybatisPlusConfig.java

@@ -32,6 +32,11 @@ import org.springframework.transaction.annotation.EnableTransactionManagement;
 @PropertySource(value = "classpath:common-mybatis.yml", factory = YmlPropertySourceFactory.class)
 public class MybatisPlusConfig {
 
+    /**
+     * 组装 MyBatis-Plus 核心拦截器链。
+     *
+     * @return MyBatis-Plus 拦截器
+     */
     @Bean
     public MybatisPlusInterceptor mybatisPlusInterceptor() {
         MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();