fix(web-ui): drop noisy session model auto-migration toasts

src/web-ui/src/flow_chat/services/AgenticEventListener.ts

@@ -222,7 +222,7 @@ export class AgenticEventListener {
 
       if (callbacks.onSessionModelAutoMigrated) {
         const unlisten = agentAPI.onSessionModelAutoMigrated((event) => {
-          logger.warn('Session model auto-migrated', event);
+          logger.debug('Session model auto-migrated', event);
           callbacks.onSessionModelAutoMigrated?.(event);
         });
         this.unlistenFunctions.push(unlisten);
@@ -263,4 +263,3 @@ export class AgenticEventListener {
 }
 
 export const agenticEventListener = new AgenticEventListener();
-

src/web-ui/src/flow_chat/services/flow-chat-manager/EventHandlerModule.ts

@@ -32,10 +32,6 @@ import { MCPAPI } from '@/infrastructure/api/service-api/MCPAPI';
 import { ACPClientAPI, type AcpPermissionRequestEvent } from '@/infrastructure/api/service-api/ACPClientAPI';
 import { globalEventBus } from '@/infrastructure/event-bus';
 import type { FlowChatContext, DialogTurn, ModelRound, FlowToolItem } from './types';
-import {
-  buildSessionModelMigrationNotice,
-  shouldSuppressSessionModelMigrationNotice,
-} from '../../utils/sessionModelMigrationNotice';
 import {
   getAiErrorPresentation,
   normalizeAiErrorDetail,
@@ -46,9 +42,6 @@ import { useReviewActionBarStore } from '../../store/deepReviewActionBarStore';
 import { buildDeepReviewCapacityQueueStateFromEvent } from '../../utils/deepReviewQueueStateEvents';
 
 const pendingImageAnalysisTurns = new Map<string, string>();
-// `restore_session` and assistant bootstrap can race on the same historical
-// session, so collapse identical auto-migration toasts into one short-lived UX notice.
-const recentSessionModelMigrationNoticeTimestamps = new Map<string, number>();
 import { 
   debouncedSaveDialogTurn, 
   immediateSaveDialogTurn, 
@@ -886,33 +879,11 @@ function handleSessionTitleGenerated(event: any): void {
 }
 
 function handleSessionModelAutoMigrated(event: SessionModelAutoMigratedEvent): void {
-  const { sessionId, newModelId, reason } = event;
+  const { sessionId, newModelId } = event;
   if (!sessionId || !newModelId) return;
 
   const store = FlowChatStore.getInstance();
   store.updateSessionModelName(sessionId, newModelId);
-
-  const notice = buildSessionModelMigrationNotice(event, (key, options) =>
-    i18nService.t(key, options)
-  );
-  if (
-    shouldSuppressSessionModelMigrationNotice(
-      recentSessionModelMigrationNoticeTimestamps,
-      notice.dedupeKey
-    )
-  ) {
-    return;
-  }
-
-  notificationService.warning(notice.message, {
-    title: notice.title,
-    duration: 6000,
-    metadata: {
-      sessionId,
-      reason,
-      newModelId,
-    },
-  });
 }
 
 /**

src/web-ui/src/locales/en-US/flow-chat.json

@@ -411,16 +411,7 @@
     "temperature": "Temperature",
     "maxTokens": "Max Tokens",
     "topP": "Top P",
-    "streaming": "Streaming",
-    "autoMigrated": {
-      "title": "Model switched automatically",
-      "description": "The model previously used by this chat is no longer available. BitFun switched this chat to automatic model selection.",
-      "reasons": {
-        "modelUnavailableOnRestore": "This happened while reopening a previous chat. You can keep going, or choose a model again later.",
-        "modelReconciled": "Your model settings changed recently, so BitFun moved this chat to an available model automatically.",
-        "fallback": "BitFun selected an available model for this chat automatically."
-      }
-    }
+    "streaming": "Streaming"
   },
   "toolbar": {
     "newSession": "New Session",

src/web-ui/src/locales/zh-CN/flow-chat.json

@@ -411,16 +411,7 @@
     "temperature": "温度",
     "maxTokens": "最大令牌数",
     "topP": "Top P",
-    "streaming": "流式输出",
-    "autoMigrated": {
-      "title": "模型已自动切换",
-      "description": "当前会话之前使用的模型配置已不可用，系统已切换为自动选择模型。",
-      "reasons": {
-        "modelUnavailableOnRestore": "这是恢复历史会话时的自动处理，你可以继续使用，或稍后重新指定模型。",
-        "modelReconciled": "模型配置刚发生过调整，系统已为当前会话自动切换到可用模型。",
-        "fallback": "系统已为当前会话自动选择可用模型。"
-      }
-    }
+    "streaming": "流式输出"
   },
   "toolbar": {
     "newSession": "新建会话",

src/web-ui/src/locales/zh-TW/flow-chat.json

@@ -411,16 +411,7 @@
     "temperature": "溫度",
     "maxTokens": "最大令牌數",
     "topP": "Top P",
-    "streaming": "流式輸出",
-    "autoMigrated": {
-      "title": "模型已自動切換",
-      "description": "當前會話先前使用的模型設定已不可用，系統已切換為自動選擇模型。",
-      "reasons": {
-        "modelUnavailableOnRestore": "這是恢復歷史會話時的自動處理，你可以繼續使用，或稍後重新指定模型。",
-        "modelReconciled": "模型設定剛發生調整，系統已為當前會話自動切換到可用模型。",
-        "fallback": "系統已為當前會話自動選擇可用模型。"
-      }
-    }
+    "streaming": "流式輸出"
   },
   "toolbar": {
     "newSession": "新建會話",