feat: 支持智能体文档附件与轻量读取

- 建立文档上传、异步读取、对象存储、补偿与聊天绑定闭环

- 按智能体 20K 上下文预算选择文档片段并保留稳定引用

- 统一聊天文件卡片、类型图标、草稿恢复与可靠下载

easyflow-modules/easyflow-module-agent/src/main/java/tech/easyflow/agent/service/AgentDocumentAttachmentService.java

@@ -0,0 +1,10 @@
+package tech.easyflow.agent.service;
+
+import com.mybatisflex.core.service.IService;
+import tech.easyflow.agent.entity.AgentDocumentAttachment;
+
+/**
+ * Agent 文档附件状态账本服务。
+ */
+public interface AgentDocumentAttachmentService extends IService<AgentDocumentAttachment> {
+}

easyflow-modules/easyflow-module-agent/src/main/java/tech/easyflow/agent/service/AgentDocumentSnapshotService.java

@@ -0,0 +1,10 @@
+package tech.easyflow.agent.service;
+
+import com.mybatisflex.core.service.IService;
+import tech.easyflow.agent.entity.AgentDocumentSnapshot;
+
+/**
+ * Agent 文档快照元数据服务。
+ */
+public interface AgentDocumentSnapshotService extends IService<AgentDocumentSnapshot> {
+}

easyflow-modules/easyflow-module-agent/src/main/java/tech/easyflow/agent/service/impl/AgentDocumentAttachmentServiceImpl.java

@@ -0,0 +1,16 @@
+package tech.easyflow.agent.service.impl;
+
+import com.mybatisflex.spring.service.impl.ServiceImpl;
+import org.springframework.stereotype.Service;
+import tech.easyflow.agent.entity.AgentDocumentAttachment;
+import tech.easyflow.agent.mapper.AgentDocumentAttachmentMapper;
+import tech.easyflow.agent.service.AgentDocumentAttachmentService;
+
+/**
+ * Agent 文档附件状态账本服务实现。
+ */
+@Service
+public class AgentDocumentAttachmentServiceImpl
+        extends ServiceImpl<AgentDocumentAttachmentMapper, AgentDocumentAttachment>
+        implements AgentDocumentAttachmentService {
+}

easyflow-modules/easyflow-module-agent/src/main/java/tech/easyflow/agent/service/impl/AgentDocumentSnapshotServiceImpl.java

@@ -0,0 +1,16 @@
+package tech.easyflow.agent.service.impl;
+
+import com.mybatisflex.spring.service.impl.ServiceImpl;
+import org.springframework.stereotype.Service;
+import tech.easyflow.agent.entity.AgentDocumentSnapshot;
+import tech.easyflow.agent.mapper.AgentDocumentSnapshotMapper;
+import tech.easyflow.agent.service.AgentDocumentSnapshotService;
+
+/**
+ * Agent 文档快照元数据服务实现。
+ */
+@Service
+public class AgentDocumentSnapshotServiceImpl
+        extends ServiceImpl<AgentDocumentSnapshotMapper, AgentDocumentSnapshot>
+        implements AgentDocumentSnapshotService {
+}

easyflow-modules/easyflow-module-agent/src/main/java/tech/easyflow/agent/service/impl/AgentServiceImpl.java

@@ -195,6 +195,37 @@ public class AgentServiceImpl extends ServiceImpl<AgentMapper, Agent> implements
         }
         agent.setVisibilityScope(VisibilityScope.fromOrDefault(agent.getVisibilityScope(), VisibilityScope.PRIVATE).name());
         agent.setInteractionConfigJson(AgentInteractionConfigSupport.normalize(agent.getInteractionConfigJson()));
+        agent.setExecutionConfigJson(normalizeExecutionConfig(agent.getExecutionConfigJson()));
+    }
+
+    /**
+     * 规范并校验 Agent 运行配置中的文档上下文预算。
+     *
+     * @param source 原运行配置
+     * @return 带默认预算的运行配置
+     */
+    private Map<String, Object> normalizeExecutionConfig(Map<String, Object> source) {
+        Map<String, Object> normalized = source == null
+                ? new LinkedHashMap<>() : new LinkedHashMap<>(source);
+        Object value = normalized.get("documentContextBudgetTokens");
+        if (value == null || String.valueOf(value).isBlank()) {
+            normalized.put("documentContextBudgetTokens", 20_000);
+            return normalized;
+        }
+        try {
+            String text = String.valueOf(value).trim();
+            if (!text.matches("\\d+")) {
+                throw new NumberFormatException();
+            }
+            int budget = Integer.parseInt(text);
+            if (budget <= 0) {
+                throw new NumberFormatException();
+            }
+            normalized.put("documentContextBudgetTokens", budget);
+            return normalized;
+        } catch (NumberFormatException error) {
+            throw new BusinessException("文档上下文预算必须为正整数");
+        }
     }
 
     private void applyDraftDefaults(Agent agent) {