优化: L2统一状态机完整(ConvState持久化+事件暴露+前端status联合)

1a PerConvState.conv_state持久化(入口/reset/drop写收敛,CONV_STATE_ENABLED门控)
1b AiChatEvent加AiConvStateChanged变体,guard持app_handle在迁移点emit
1c 前端convStates真相源+停止按钮三态(status union)+MaxRoundsCard读conv_state
双轨过渡:enum视图与generating bool并行,off降级可回退

src/components/ai/MaxRoundsCard.vue

@@ -27,7 +27,7 @@
 import { ref, computed, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { useAiStore } from '../../stores/ai'
-import { pendingMaxRounds } from '../../composables/ai/useAiEvents'
+import { pendingMaxRounds, getConvState } from '../../composables/ai/useAiEvents'
 import { aiApi } from '../../api'
 
 const emit = defineEmits<{
@@ -47,6 +47,20 @@ const isViewingGenerating = computed(() =>
   store.isGenerating(store.state.activeConversationId),
 )
 
+// L2 状态机(批2 1c):达 max 可靠弹判断改读 conv_state(generating),诊断痛②看门狗误清 streaming
+// 致卡片不弹的根解。conv_state 作新增派生源,旧 isGenerating 双轨过渡兜底——conv_state 未收到
+// 时(CONV_STATE_ENABLED=off 或老后端)回退 isGenerating 判断,不强制全替防回归。
+// 注:达 max 时后端仍 generating(conv_state=generating,审批挂起期亦是 generating),故读
+// conv_state===generating 覆盖挂起态;compressed(压缩派生)也视为活跃可弹(达 max 与压缩互斥,
+// 理论不并存,此处宽放以防边界)。
+const isViewingGeneratingState = computed(() => {
+  const cs = getConvState(store.state.activeConversationId)
+  if (cs === 'generating' || cs === 'compressed') return true
+  if (cs === 'idle' || cs === 'error' || cs === 'stopping') return false
+  // conv_state 未追踪过(null)→ 回退旧 isGenerating bool 判断
+  return isViewingGenerating.value
+})
+
 // pendingMaxRounds(达 max 事件置的挂起 convId)+ 当前视图正在生成(防切走后误显)双重守卫。
 // TD-260621-02 per-conv:pendingMaxRounds 存挂起 convId(string|null),精确比对
 // activeConversationId —— 仅当挂起会话 === 当前展示会话时显操作卡,F-09 并发下不会错显于其他会话。
@@ -56,7 +70,7 @@ const maxRoundsActing = ref(false)
 const showMaxRoundsCard = computed(() =>
   !!pendingMaxRounds.value
   && pendingMaxRounds.value === store.state.activeConversationId
-  && isViewingGenerating.value,
+  && isViewingGeneratingState.value,
 )
 
 /** 点继续:调 ai_continue_loop。后端续 max_iterations 轮(iteration 从 0 重计)。