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-ui-admin/app/src/views/ai/agents/components/AgentTryoutPanel.vue

@@ -1,5 +1,7 @@
 <script setup lang="ts">
 import type {
+  ChatDocumentAttachment,
+  ChatImageAttachment,
   ChatTimelineMessageItem,
   ChatTimelineToolApprovalPayload,
 } from '@easyflow/common-ui';
@@ -19,7 +21,10 @@ import { copyTextToClipboard } from '@easyflow/utils';
 import { ElButton, ElMessage } from 'element-plus';
 
 import AiChatPanel from '#/components/ai-chat/AiChatPanel.vue';
-import { loadAgentChatImage } from '#/components/ai-chat/mediaApi';
+import {
+  loadAgentChatDocument,
+  loadAgentChatImage,
+} from '#/components/ai-chat/mediaApi';
 import { useAgentComposerDraft } from '#/components/ai-chat/useAgentComposerDraft';
 
 import { approveAgentRun, rejectAgentRun } from '../api';
@@ -104,6 +109,10 @@ async function handleSend(prompt: string) {
     ElMessage.warning('图片上传完成后再发送');
     return;
   }
+  if (composer.documents.processing.value) {
+    ElMessage.warning('文档读取完成后再发送');
+    return;
+  }
   const failedImage = composer.images.items.value.find(
     (item) => item.status === 'error',
   );
@@ -111,9 +120,20 @@ async function handleSend(prompt: string) {
     ElMessage.error(failedImage.error || '请处理上传失败的图片');
     return;
   }
+  const failedDocument = composer.documents.items.value.find(
+    (item) => item.status === 'error',
+  );
+  if (failedDocument) {
+    ElMessage.error(failedDocument.error || '请处理读取失败的文档');
+    return;
+  }
   await composer.flush();
   await sendDraft({
     ...getDraftContext(),
+    documentUploadIds: composer.documents.uploadIds.value,
+    documents: composer.documents.readyItems.value.map((item) => ({
+      ...item,
+    })),
     prompt,
     imageUploadIds: composer.images.uploadIds.value,
     images: composer.images.readyItems.value.map((item) => ({ ...item })),
@@ -188,7 +208,7 @@ async function handleClearSession() {
   }
 }
 
-async function handleAddFiles(files: File[]) {
+async function handleAddImageFiles(files: File[]) {
   if (!props.agent.id) {
     ElMessage.warning('请先保存智能体');
     return;
@@ -205,7 +225,24 @@ async function handleAddFiles(files: File[]) {
   composer.scheduleSave();
 }
 
-async function handleRetryImage(item: any) {
+async function handleAddDocumentFiles(files: File[]) {
+  if (!props.agent.id) {
+    ElMessage.warning('请先保存智能体');
+    return;
+  }
+  await composer.ensureSession();
+  const rejected = await composer.documents.addFiles(files, {
+    agentId: String(props.agent.id),
+    mode: 'DRAFT',
+    sessionId: composer.sessionId.value,
+  });
+  if (rejected > 0) {
+    ElMessage.warning('每轮最多添加 3 份文档');
+  }
+  composer.scheduleSave();
+}
+
+async function handleRetryImage(item: ChatImageAttachment) {
   await composer.images.retry(item, {
     agentId: String(props.agent.id),
     mode: 'DRAFT',
@@ -214,7 +251,7 @@ async function handleRetryImage(item: any) {
   composer.scheduleSave();
 }
 
-async function handleRemoveImage(item: any) {
+async function handleRemoveImage(item: ChatImageAttachment) {
   try {
     await composer.images.remove(item);
     composer.scheduleSave();
@@ -223,6 +260,24 @@ async function handleRemoveImage(item: any) {
   }
 }
 
+async function handleRetryDocument(item: ChatDocumentAttachment) {
+  await composer.documents.retry(item, {
+    agentId: String(props.agent.id),
+    mode: 'DRAFT',
+    sessionId: composer.sessionId.value,
+  });
+  composer.scheduleSave();
+}
+
+async function handleRemoveDocument(item: ChatDocumentAttachment) {
+  try {
+    await composer.documents.remove(item);
+    composer.scheduleSave();
+  } catch (error) {
+    ElMessage.error(error instanceof Error ? error.message : '文档删除失败');
+  }
+}
+
 function handleStop() {
   if (!loading.value) {
     return;
@@ -275,6 +330,8 @@ async function handleReject(payload: ChatTimelineToolApprovalPayload) {
     closable
     :messages="[]"
     :loading="loading"
+    :documents="composer.documents.items.value"
+    :document-loader="loadAgentChatDocument"
     :images="composer.images.items.value"
     :image-enabled="imageEnabled"
     :image-loader="loadAgentChatImage"
@@ -282,8 +339,11 @@ async function handleReject(payload: ChatTimelineToolApprovalPayload) {
     :approval-loading="approvalLoading"
     @send="handleSend"
     @update:model-value="handleDraftTextInput"
-    @add-files="handleAddFiles"
+    @add-files="handleAddImageFiles"
+    @add-document-files="handleAddDocumentFiles"
+    @remove-document="handleRemoveDocument"
     @remove-image="handleRemoveImage"
+    @retry-document="handleRetryDocument"
     @retry-image="handleRetryImage"
     @stop="handleStop"
     @approve="handleApprove"
@@ -314,6 +374,7 @@ async function handleReject(payload: ChatTimelineToolApprovalPayload) {
       <ChatTimeline
         v-else
         :items="timelineItems"
+        :document-loader="loadAgentChatDocument"
         :image-loader="loadAgentChatImage"
         empty-text="输入问题试运行当前智能体"
         :approval-loading="approvalLoading"