feat: 应用名称更新为灵可析并增强 Chat 功能

- 更新 Android/iOS 应用名称和图标为灵可析
- Chat 支持取消正在运行的 Agent 对话
- 改进 ChatBloc 状态管理（区分发送/等待/流式/取消状态）
- HomeScreen 支持外部注入 ChatBloc 和显示等待指示器
- 后端 Agent 运行服务优化（消息处理、usage 追踪）
- 补充相关单元测试和 Widget 测试

apps/lib/features/chat/presentation/bloc/chat_bloc.dart

@@ -11,7 +11,11 @@ import '../../data/services/ag_ui_service.dart';
 
 class ChatState {
   final List<ChatListItem> items;
-  final bool isLoading;
+  final bool isSending;
+  final bool isWaitingFirstToken;
+  final bool isStreaming;
+  final bool isCancelling;
+  final bool isLoadingHistory;
   final String? currentMessageId;
   final String? error;
   final DateTime? oldestLoadedDate;
@@ -19,18 +23,33 @@ class ChatState {
 
   const ChatState({
     this.items = const [],
-    this.isLoading = false,
+    this.isSending = false,
+    this.isWaitingFirstToken = false,
+    this.isStreaming = false,
+    this.isCancelling = false,
+    this.isLoadingHistory = false,
     this.currentMessageId,
     this.error,
     this.oldestLoadedDate,
     this.hasEarlierHistory = false,
   });
 
+  bool get isLoading =>
+      isSending ||
+      isWaitingFirstToken ||
+      isStreaming ||
+      isCancelling ||
+      isLoadingHistory;
+
   static const _unset = Object();
 
   ChatState copyWith({
     List<ChatListItem>? items,
-    bool? isLoading,
+    bool? isSending,
+    bool? isWaitingFirstToken,
+    bool? isStreaming,
+    bool? isCancelling,
+    bool? isLoadingHistory,
     Object? currentMessageId = _unset,
     Object? error = _unset,
     Object? oldestLoadedDate = _unset,
@@ -38,7 +57,11 @@ class ChatState {
   }) {
     return ChatState(
       items: items ?? this.items,
-      isLoading: isLoading ?? this.isLoading,
+      isSending: isSending ?? this.isSending,
+      isWaitingFirstToken: isWaitingFirstToken ?? this.isWaitingFirstToken,
+      isStreaming: isStreaming ?? this.isStreaming,
+      isCancelling: isCancelling ?? this.isCancelling,
+      isLoadingHistory: isLoadingHistory ?? this.isLoadingHistory,
       currentMessageId: currentMessageId == _unset
           ? this.currentMessageId
           : currentMessageId as String?,
@@ -72,12 +95,36 @@ class ChatBloc extends Cubit<ChatState> {
   void _handleEvent(AgUiEvent event) {
     switch (event.type) {
       case AgUiEventType.runStarted:
-        emit(state.copyWith(isLoading: true, error: null));
+        emit(
+          state.copyWith(
+            isSending: false,
+            isWaitingFirstToken: true,
+            isCancelling: false,
+            error: null,
+          ),
+        );
       case AgUiEventType.runFinished:
-        emit(state.copyWith(isLoading: false, currentMessageId: null));
+        emit(
+          state.copyWith(
+            isSending: false,
+            isWaitingFirstToken: false,
+            isStreaming: false,
+            isCancelling: false,
+            currentMessageId: null,
+          ),
+        );
       case AgUiEventType.runError:
         final errorEvent = event as RunErrorEvent;
-        emit(state.copyWith(isLoading: false, error: errorEvent.message));
+        emit(
+          state.copyWith(
+            isSending: false,
+            isWaitingFirstToken: false,
+            isStreaming: false,
+            isCancelling: false,
+            currentMessageId: null,
+            error: errorEvent.message,
+          ),
+        );
       case AgUiEventType.textMessageStart:
         _handleTextMessageStart(event as TextMessageStartEvent);
       case AgUiEventType.textMessageContent:
@@ -115,6 +162,8 @@ class ChatBloc extends Cubit<ChatState> {
       state.copyWith(
         items: [...state.items, newMessage],
         currentMessageId: startEvent.messageId,
+        isWaitingFirstToken: false,
+        isStreaming: true,
       ),
     );
   }
@@ -136,7 +185,13 @@ class ChatBloc extends Cubit<ChatState> {
       }
       return item;
     }).toList();
-    emit(state.copyWith(items: updatedItems, currentMessageId: null));
+    emit(
+      state.copyWith(
+        items: updatedItems,
+        currentMessageId: null,
+        isStreaming: false,
+      ),
+    );
   }
 
   void _handleToolCallStart(ToolCallStartEvent startEvent) {
@@ -319,20 +374,50 @@ class ChatBloc extends Cubit<ChatState> {
       timestamp: DateTime.now(),
       sender: MessageSender.user,
     );
-    emit(state.copyWith(items: [...state.items, userMessage]));
-    await _service.sendMessage(content);
+    emit(
+      state.copyWith(
+        items: [...state.items, userMessage],
+        isSending: true,
+        isWaitingFirstToken: true,
+        isStreaming: false,
+        isCancelling: false,
+        error: null,
+      ),
+    );
+    try {
+      await _service.sendMessage(content);
+    } catch (error) {
+      emit(
+        state.copyWith(
+          isSending: false,
+          isWaitingFirstToken: false,
+          isStreaming: false,
+          isCancelling: false,
+          error: error.toString(),
+        ),
+      );
+    }
   }
 
   Future<void> loadHistory() async {
-    if (state.isLoading) return;
-    await _service.loadHistory();
+    if (state.isLoadingHistory) return;
+    emit(state.copyWith(isLoadingHistory: true));
+    try {
+      await _service.loadHistory();
+    } finally {
+      emit(state.copyWith(isLoadingHistory: false));
+    }
   }
 
   Future<void> loadMoreHistory() async {
-    if (state.isLoading || !state.hasEarlierHistory) return;
+    if (state.isLoadingHistory || !state.hasEarlierHistory) return;
     if (state.oldestLoadedDate == null) return;
-
-    await _service.loadHistory(beforeDate: state.oldestLoadedDate);
+    emit(state.copyWith(isLoadingHistory: true));
+    try {
+      await _service.loadHistory(beforeDate: state.oldestLoadedDate);
+    } finally {
+      emit(state.copyWith(isLoadingHistory: false));
+    }
   }
 
   Future<void> approveToolCall(String toolCallId) async {
@@ -355,7 +440,16 @@ class ChatBloc extends Cubit<ChatState> {
       }
       return item;
     }).toList();
-    emit(state.copyWith(items: updatedItems, isLoading: true, error: null));
+    emit(
+      state.copyWith(
+        items: updatedItems,
+        isSending: false,
+        isWaitingFirstToken: true,
+        isStreaming: false,
+        isCancelling: false,
+        error: null,
+      ),
+    );
     try {
       await _service.approveToolCall(
         toolCallId: target.callId,
@@ -375,7 +469,10 @@ class ChatBloc extends Cubit<ChatState> {
       emit(
         state.copyWith(
           items: failedItems,
-          isLoading: false,
+          isSending: false,
+          isWaitingFirstToken: false,
+          isStreaming: false,
+          isCancelling: false,
           error: error.toString(),
         ),
       );
@@ -386,6 +483,31 @@ class ChatBloc extends Cubit<ChatState> {
     return _service.transcribeAudio(filePath);
   }
 
+  Future<bool> cancelCurrentRun() async {
+    if (!(state.isWaitingFirstToken ||
+        state.isStreaming ||
+        state.isCancelling)) {
+      return false;
+    }
+    emit(state.copyWith(isCancelling: true, error: null));
+    try {
+      await _service.cancelCurrentRun();
+      emit(
+        state.copyWith(
+          isSending: false,
+          isWaitingFirstToken: false,
+          isStreaming: false,
+          isCancelling: false,
+          currentMessageId: null,
+        ),
+      );
+      return true;
+    } catch (error) {
+      emit(state.copyWith(isCancelling: false, error: error.toString()));
+      return false;
+    }
+  }
+
   void clearError() {
     emit(state.copyWith(error: null));
   }