优化: 批A前端(timer所有权+会话族+审批conv-scoped+FilePreview+失败反馈)

A1-B1 timer所有权:新建 useTimerOwnership composable(每实例独立ref+onUnmounted清理)+ useToast _timer 下沉 + Ideas debounce 补清理(治跨实例串扰)

A1-B2 FilePreview:reqSeq 双计数器守卫(loadFile/loadDiff 最新seq才写,防乱序覆盖)+ mermaid securityLevel strict + filePath 比对(防跨文件SVG注入)

A1-B3 会话族:load_more 滚顶加载接线(switch透传has_more/earliest_seq+prepend去重+scrollTop恢复)+ switch失败保留视图+报错(仅对话不存在才create-new)+ new/delete失败反馈(withConvOp helper收敛)+ delete清ai_messages孤儿

A1-B5前端契约:isToolFailure 三处加 success===false 判定(useToolCard/ToolResultBody/ToolCard,git只读失败不再绿框)

A2-B10 审批conv-scoped:pendingApprovals 补conversationId + cleanup 按convId filter + 移除全局清(AiError不再误清其他conv)+ :676 dir auth filter方向修

usage打标前端:is_estimated 字段+事件透传+MessageList『估算』角标(详情面板说明)

A2-B9前端:clearChat try/catch 错误气泡

src/components/project/FilePreview.vue

@@ -72,8 +72,8 @@
         </div>
       </div>
 
-      <!-- Markdown 渲染(marked + DOMPurify + 代码高亮) -->
-      <div v-else-if="isMarkdown" class="preview-md ai-md" v-html="renderedMd"></div>
+      <!-- Markdown 渲染(marked + DOMPurify + 代码高亮;mermaid 块渲染后转成图) -->
+      <div v-else-if="isMarkdown" ref="previewMdRef" class="preview-md ai-md" v-html="renderedMd"></div>
 
       <!-- 文本/代码(highlight.js 语法高亮 + 行号;非 diff 模式时显示) -->
       <div v-else class="preview-code-scroll">
@@ -87,7 +87,7 @@
 </template>
 
 <script setup lang="ts">
-import { ref, watch, computed, onUnmounted } from 'vue'
+import { ref, watch, computed, onUnmounted, nextTick } from 'vue'
 import { moduleApi } from '@/api/module'
 import hljs from 'highlight.js/lib/common'
 import { useMarkdown, useRendered } from '@/composables/useMarkdown'
@@ -127,6 +127,14 @@ const showDiff = ref(false)
 const diffContent = ref('')
 const diffLoading = ref(false)
 
+/** 请求序号守卫:loadFile/loadDiff 各自单调递增,await 返回后校验仍是"最新 seq"才写状态,
+ * 否则丢弃(快速切文件/切视图时旧响应晚到不覆盖新内容)。
+ * 注:loadFile 与 loadDiff 分用两个计数器 —— 若共用一个,loadDiff 自增会让在途的 loadFile
+ * 变为 stale,其 finally 不再复位 loading,导致内容加载态卡死。分开后各自独立互不干扰;
+ * 文件切换(watch)时额外自增 diffReqSeq,使在途 diff 请求对旧文件失效。 */
+let fileReqSeq = 0 // loadFile 请求序号(单调递增)
+let diffReqSeq = 0 // loadDiff 请求序号(单调递增)
+
 interface DiffLine {
   type: 'add' | 'del' | 'ctx' | 'hdr'
   prefix: string
@@ -179,14 +187,17 @@ function toggleDiff() {
 
 async function loadDiff() {
   if (!props.moduleId || !props.filePath) return
+  const seq = ++diffReqSeq // 捕获本次请求序号
   diffLoading.value = true
   try {
     const res = await moduleApi.getModuleFileDiff(props.moduleId, props.filePath)
+    if (seq !== diffReqSeq) return // 旧响应晚到,丢弃不覆盖
     diffContent.value = res.diff || ''
   } catch {
+    if (seq !== diffReqSeq) return
     diffContent.value = ''
   } finally {
-    diffLoading.value = false
+    if (seq === diffReqSeq) diffLoading.value = false
   }
 }
 
@@ -222,6 +233,48 @@ const isMarkdown = computed(() => {
 /** Markdown 渲染(复用 useRendered,含 marked + DOMPurify + 代码高亮)。 */
 const { rendered: renderedMd, ensureLoaded: ensureMdLoaded } = useRendered(() => content.value)
 
+// ═══ Mermaid 渲染:markdown 里的 ```mermaid 块渲染为图(按需动态 import,不增主 bundle)═══
+const previewMdRef = ref<HTMLElement | null>(null)
+let mermaidInstance: any = null
+let mermaidSeq = 0
+async function renderMermaidBlocks() {
+  const el = previewMdRef.value
+  if (!el) return
+  const targetPath = props.filePath // 捕获渲染目标文件,防跨文件滞后注入
+  const blocks = el.querySelectorAll<HTMLElement>('pre code.language-mermaid')
+  if (blocks.length === 0) return
+  if (!mermaidInstance) {
+    const mod = await import('mermaid')
+    mermaidInstance = mod.default
+    // securityLevel 'strict':mermaid 自行转义渲染输出(禁 raw HTML/URL 注入),防 XSS。
+    // 代价:node 内嵌 HTML label(如 <br/>/HTML 实体)在 'strict' 下被当纯文本显示,
+    // 原 'loose' 能渲染的这类图例会回归为文本(安全优先,属预期收紧)。
+    mermaidInstance.initialize({ startOnLoad: false, theme: 'dark', securityLevel: 'strict' })
+  }
+  // 懒加载 mermaid 期间文件可能已切换(旧 DOM 已卸载),直接丢弃本轮
+  if (props.filePath !== targetPath) return
+  for (const block of Array.from(blocks)) {
+    if (block.closest('.mermaid-rendered')) continue
+    const code = (block.textContent ?? '').trim()
+    if (!code) continue
+    try {
+      const { svg } = await mermaidInstance.render(`mermaid-file-${++mermaidSeq}`, code)
+      if (props.filePath !== targetPath) return // 渲染期间文件已切换,丢弃旧图不注入
+      const holder = document.createElement('div')
+      holder.className = 'mermaid-rendered'
+      holder.innerHTML = svg
+      block.closest('pre')?.replaceWith(holder)
+    } catch (e) {
+      if (props.filePath !== targetPath) return
+      console.error('[FilePreview] mermaid 渲染失败:', e)
+    }
+  }
+}
+watch(renderedMd, async () => {
+  await nextTick()
+  await renderMermaidBlocks()
+}, { immediate: true })
+
 const isImage = computed(() => {
   if (!props.filePath) return false
   const lower = props.filePath.toLowerCase()
@@ -230,6 +283,7 @@ const isImage = computed(() => {
 
 /** 拉文件内容 + 高亮渲染。 */
 async function loadFile() {
+  const seq = ++fileReqSeq // 捕获本次请求序号(文件切换会使旧请求失效)
   if (!props.filePath) {
     content.value = ''
     htmlContent.value = ''
@@ -248,6 +302,7 @@ async function loadFile() {
   }
   try {
     const res = await moduleApi.readModuleFile(props.moduleId, props.filePath)
+    if (seq !== fileReqSeq) return // 旧响应晚到,丢弃不覆盖新文件内容
     fileSize.value = res.size
     truncated.value = res.truncated
     isBinary.value = res.is_binary
@@ -261,10 +316,11 @@ async function loadFile() {
       htmlContent.value = ''
       try {
         const { convertFileSrc } = await import('@tauri-apps/api/core')
+        if (seq !== fileReqSeq) return // import 期间文件已切换,不写入旧图
         const abs = joinPath(props.moduleRootPath, props.filePath)
         imageUrl.value = convertFileSrc(abs)
       } catch {
-        imageUrl.value = null
+        if (seq === fileReqSeq) imageUrl.value = null
       }
     } else {
       content.value = res.content
@@ -283,9 +339,10 @@ async function loadFile() {
       }
     }
   } catch (e) {
+    if (seq !== fileReqSeq) return // 旧请求报错也不覆盖新状态
     error.value = e instanceof Error ? e.message : String(e)
   } finally {
-    loading.value = false
+    if (seq === fileReqSeq) loading.value = false
   }
 }
 
@@ -321,8 +378,10 @@ function gitStatusLabel(status: string): string {
 }
 
 watch(() => [props.moduleId, props.filePath], () => {
+  diffReqSeq++ // 文件切换,使在途 diff 请求失效(旧文件 diff 晚到不写入)
   showDiff.value = false
   diffContent.value = ''
+  diffLoading.value = false
   loadFile()
 }, { immediate: true })
 
@@ -438,6 +497,14 @@ onUnmounted(() => {
   border-radius: var(--df-radius-sm, 4px);
 }
 
+/* Markdown 视图:独立滚动容器(preview-body 是 overflow:hidden,不设 overflow 会被裁剪无法滚) */
+.preview-md {
+  flex: 1;
+  min-height: 0;
+  overflow: auto;
+  padding: 14px 16px;
+}
+
 .preview-code {
   margin: 0;
   padding: 14px 16px;