优化: 会话状态 per-conv 化与交互守卫

- 待审批跨会话 per-conv 合并,审批类事件全局放行
- 看门狗/重试计数/流式残段按会话键控迁移
- 输入草稿与子代理完成卡数据按会话隔离
- 切换兜底 activeId,收敛守卫防幽灵气泡
- 发送错误按限流/额度/网络分类文案

src/composables/ai/useAiPanel.ts

@@ -14,7 +14,7 @@ import { useAppSettingsStore } from '@/stores/appSettings'
 import { state } from '@/stores/ai'
 import { setStreaming } from './streamingGuard'
 import { syncHighRiskTools } from './useToolApproval'
-import { nextMsgId } from './aiShared'
+import { nextMsgId, setConvPendingApprovals } from './aiShared'
 import { t } from '@/i18n/i18n-helpers'
 import type { AiMessage, AiProviderConfig } from '@/api/types'
 
@@ -188,7 +188,12 @@ async function clearChat() {
     await aiApi.clearChat()
     state.messages = []
     state.currentText = ''
-    state.pendingApprovals = []
+    // 清空的是当前会话:其 per-conv 挂起集合同步清(其他会话集合不动)
+    if (state.activeConversationId) {
+      setConvPendingApprovals(state.activeConversationId, [])
+    } else {
+      state.pendingApprovals = []
+    }
     setStreaming(false, { reason: 'clearChat' })
   } catch (e) {
     // A2-B9(G3.2):清空失败需反馈,原裸 await 失败静默(异常进 unhandledrejection,用户无感)。