重构：使用 MyBatis-Flex 迁移应用 ORM

将应用自管表的 JdbcClient 数据访问迁移为实体、Mapper、构造器查询和必要的显式 SQL。

保留 AgentScope 自管表及原有业务语义，并补充事务、查询与数据库集成测试。

server/src/main/resources/mapper/ArtifactMapper.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE mapper
+        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
+        "https://mybatis.org/dtd/mybatis-3-mapper.dtd">
+<mapper namespace="tech.easyflow.manuagent.mapper.ArtifactMapper">
+
+    <!--
+        PostgreSQL 的 INSERT ... RETURNING 属于会修改数据的查询语句。
+        affectData 与 flushCache 确保 MyBatis 按 DML 事务语义处理并清理一级缓存。
+    -->
+    <select id="upsert"
+            resultType="tech.easyflow.manuagent.entity.ArtifactEntity"
+            affectData="true"
+            flushCache="true">
+        INSERT INTO app.artifact(
+            id, project_id, run_id, kind, name, relative_path, mime_type,
+            size_bytes, sha256, metadata_json)
+        VALUES (
+            #{artifact.id, typeHandler=tech.easyflow.manuagent.typehandler.UuidTypeHandler},
+            #{artifact.projectId, typeHandler=tech.easyflow.manuagent.typehandler.UuidTypeHandler},
+            #{artifact.runId, typeHandler=tech.easyflow.manuagent.typehandler.UuidTypeHandler},
+            #{artifact.kind}, #{artifact.name}, #{artifact.relativePath}, #{artifact.mimeType},
+            #{artifact.sizeBytes}, #{artifact.sha256},
+            #{artifact.metadataJson, jdbcType=OTHER, typeHandler=tech.easyflow.manuagent.typehandler.JsonbStringTypeHandler})
+        ON CONFLICT (project_id, relative_path) DO UPDATE SET
+            run_id = EXCLUDED.run_id,
+            kind = EXCLUDED.kind,
+            name = EXCLUDED.name,
+            mime_type = EXCLUDED.mime_type,
+            size_bytes = EXCLUDED.size_bytes,
+            sha256 = EXCLUDED.sha256,
+            metadata_json = EXCLUDED.metadata_json,
+            published_at = CURRENT_TIMESTAMP
+        <!-- 发布接口只需要产物视图字段，下载字段由独立下载查询按需读取。 -->
+        RETURNING id, project_id, run_id, kind, name, size_bytes, metadata_json, published_at
+    </select>
+</mapper>