修复: 审批不超时+重启恢复 + 其他小改

- APPROVAL_TIMEOUT_MS=Infinity(已决策:审批不做超时)
- V33 迁移: ai_conversations 加 pending_approvals 列
- save_conversation 持久化 pending_approvals
- ai_conversation_switch 从 DB 恢复 pending_approvals
- switchConversation 加 try/catch(对话不存在→建新)
- @项目 关联添加取消按钮(×)
- TopBar 底部无标题时图标右对齐
- TaskDetail.vue 删除重复 case

src/components/ai/TopBar.vue

@@ -538,26 +538,26 @@ onBeforeUnmount(() => {
 .ai-bottom-tools {
   display: flex;
   align-items: center;
-  justify-content: space-between;
+
   padding: 0 14px 4px;
 }
 .ai-bottom-title {
   font-size: 11px;
   color: var(--df-text-secondary);
   min-width: 0;
-  flex: 1;
-  margin-right: 8px;
+  margin-right: auto;
+
 }
 .ai-bottom-tools-right {
   display: flex;
   align-items: center;
   gap: 4px;
   flex-shrink: 0;
+  margin-left: auto;
 }
 /* ═══ Provider Bar (header 中间区) ═══ */
 .ai-provider-bar {
   display: inline-flex;
-  align-items: center;
   gap: 4px;
   font-size: 11px;
   color: var(--df-text-secondary);