feat: mention 支持 workspace 的文件

在保留附件 mention 的同时，将共享 `workspace` 文件纳入候选范围；并将 `@` 空查询时的候选列表改为空，仅在继续输入后再执行筛选，避免工作区文件过多时直接铺满下拉面板

docs/develop-guides/roadmap.md

@@ -57,6 +57,7 @@
 
 ### 修复
 
+- 优化 Agent 输入框 mention 行为：在保留附件 mention 的同时，将共享 `workspace` 文件纳入候选范围；并将 `@` 空查询时的候选列表改为空，仅在继续输入后再执行筛选，避免工作区文件过多时直接铺满下拉面板
 - 为前端工作台文件树补齐文件删除能力：`/api/viewer/filesystem/file` 新增删除接口，`AgentPanel` 文件节点新增删除按钮与确认交互，删除后会同步刷新树与预览状态
 - 调整前端工作台文件预览交互：恢复默认侧边/弹窗预览，并新增显式“全屏预览”入口；全屏模式下由预览内容直接覆盖整页，仅保留右上角悬浮关闭按钮；
 - 统一 Agent Panel 文件预览与消息区交付物预览组件：两处改为复用同一套 `AgentFilePreview` 预览实现，并为交付物预览补齐与工作台一致的“全屏预览”入口

web/src/components/AgentChatComponent.vue

@@ -456,6 +456,7 @@ watch(hasAgentStateContent, (newVal, oldVal) => {
 })
 const { mentionConfig } = useAgentMentionConfig({
   currentAgentState,
+  currentThreadFiles,
   currentThreadAttachments,
   configurableItems,
   agentConfig,

web/src/components/MessageInputComponent.vue

@@ -252,6 +252,7 @@ const updateMentionItems = (query = '') => {
 
   const lowerQuery = query.toLowerCase()
   const { files = [], knowledgeBases = [], mcps = [], skills = [], subagents = [] } = props.mention
+  const workspacePrefix = '/home/gem/user-data/workspace/'
 
   const filterItems = (list) =>
     list.filter((item) => {
@@ -270,6 +271,13 @@ const updateMentionItems = (query = '') => {
       )
     })
 
+  const filterFileItems = (list) => {
+    if (!query) {
+      return list.filter((item) => !String(item.value || '').startsWith(workspacePrefix))
+    }
+    return filterItems(list)
+  }
+
   const fileItems = files.map((f) => {
     const path = f.path || ''
     const fileName = path.split('/').pop() || path
@@ -333,7 +341,7 @@ const updateMentionItems = (query = '') => {
   })
 
   mentionItems.value = {
-    files: filterItems(fileItems),
+    files: filterFileItems(fileItems),
     knowledgeBases: filterItems(knowledgeItems),
     mcps: filterItems(mcpItems),
     skills: filterItems(skillItems),

web/src/composables/useAgentMentionConfig.js

@@ -2,6 +2,7 @@ import { computed } from 'vue'
 
 export function useAgentMentionConfig({
   currentAgentState,
+  currentThreadFiles,
   currentThreadAttachments,
   configurableItems,
   agentConfig,
@@ -13,6 +14,7 @@ export function useAgentMentionConfig({
     const rawFiles = currentAgentState.value?.files || {}
     const files = []
     const seenPaths = new Set()
+    const workspaceFiles = Array.isArray(currentThreadFiles?.value) ? currentThreadFiles.value : []
 
     const pushFile = (entry) => {
       const path = entry?.path || ''
@@ -60,6 +62,18 @@ export function useAgentMentionConfig({
       })
     })
 
+    workspaceFiles.forEach((entry) => {
+      const path = entry?.path || ''
+      if (!path.startsWith('/home/gem/user-data/workspace/') || entry?.is_dir) return
+      pushFile({
+        path,
+        size: entry.size,
+        modified_at: entry.modified_at,
+        artifact_url: entry.artifact_url,
+        file_name: entry.name
+      })
+    })
+
     const configItems = configurableItems.value || {}
     const currentConfig = agentConfig.value || {}
     const allowedKbNames = new Set()