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/ToolCard.vue

@@ -213,6 +213,8 @@ const isFailed = computed(() => {
     if (r && typeof r.exit_code === 'number') return r.exit_code !== 0
     if (r) return true
   }
+  // A1-B5:git 只读工具失败返 {success:false,error}(结构化非 Err),通用分支识别
+  if (r && r.success === false) return true
   if (!r) {
     const raw = typeof tc.result === 'string' ? tc.result : ''
     if (!raw) return false
@@ -251,7 +253,7 @@ const diffLines = computed(() => parseDiffLines(props.tc.diff))
   display: flex; align-items: center; gap: 6px;
   padding: 4px 10px 8px 42px; font-size: 11px; color: var(--df-danger);
 }
-.ai-tool-rejected-icon { font-weight: 700; }
+.ai-tool-rejected-icon { font-weight: 500; }
 
 /* -- 卡片折叠态(running/pending 始终展开,completed/rejected 默认折叠为单行 header) -- */
 .ai-tool-card--collapsed .ai-tool-header { cursor: pointer; }