refactor(agent): 优化天气卡片背景渐变逻辑并移除未使用的BLE订阅

将天气卡片的背景渐变逻辑提取为独立方法，根据天气类型返回不同的渐变颜色
移除agent_controller中未使用的BLE事件订阅代码

lib/modules/agent/controllers/agent_controller.dart

@@ -160,7 +160,7 @@ class AgentController extends GetxController {
     _setupScrollListener(); //设置滚动监听器
     _loadChatHistory(); //加载聊天历史记录
     _subscribeToEvents(); //订阅代理服务事件
-    _subscribeToBleEvents(); //订阅BLE事件
+    // _subscribeToBleEvents(); //订阅BLE事件
     _initMusicStatus(); //初始化音乐状态
     _setupMediaSessionCallbacks(); //设置媒体会话回调
     _setupTextInputListener(); //设置文本输入监听器

lib/modules/agent/views/weather_card.dart

@@ -25,17 +25,7 @@ Widget buildWeatherContent(BuildContext context, String city,
       Container(
         padding: EdgeInsets.all(16.w),
         decoration: BoxDecoration(
-          gradient: isDarkMode
-              ? const LinearGradient(
-                  begin: Alignment.topLeft,
-                  end: Alignment.bottomRight,
-                  colors: [Color(0xFF1E40AF), Color(0xFF1E3A8A)],
-                )
-              : const LinearGradient(
-                  begin: Alignment.topLeft,
-                  end: Alignment.bottomRight,
-                  colors: [Color(0xFF60A5FA), Color(0xFF3B82F6)],
-                ),
+          gradient: _getWeatherGradient(now['dayweather'] ?? '', isDarkMode),
           borderRadius: BorderRadius.circular(12.r),
           boxShadow: [
             BoxShadow(
@@ -63,7 +53,7 @@ Widget buildWeatherContent(BuildContext context, String city,
                         color: Colors.white,
                       ),
                     ),
-                    SizedBox(height: 4),
+                    SizedBox(height: 4.w),
                     Text(
                       _getWeatherDescriptionTranslation(now["dayweather"]),
                       style: TextStyle(
@@ -483,3 +473,90 @@ IconData getWeatherIcon(String description) {
   // 默认或未知天气
   return Icons.help_outline;
 }
+
+/// 根据天气类型获取背景渐变颜色
+LinearGradient _getWeatherGradient(String weather, bool isDarkMode) {
+  final weatherType = weather.trim();
+
+  // 晴天 - 温暖的橙黄色
+  if (['晴', '少云', '晴间多云'].any((sunny) => weatherType.contains(sunny))) {
+    return LinearGradient(
+      begin: Alignment.topLeft,
+      end: Alignment.bottomRight,
+      colors: isDarkMode
+          ? [Color(0xFFFF8A00), Color(0xFFE65100)] // 深色模式：深橙色
+          : [Color(0xFFFFB74D), Color(0xFFFF9800)], // 浅色模式：亮橙色
+    );
+  }
+
+  // 多云/阴天 - 灰蓝色
+  if (['多云', '阴'].any((cloudy) => weatherType.contains(cloudy))) {
+    return LinearGradient(
+      begin: Alignment.topLeft,
+      end: Alignment.bottomRight,
+      colors: isDarkMode
+          ? [Color(0xFF455A64), Color(0xFF37474F)] // 深色模式：深灰蓝
+          : [Color(0xFF78909C), Color(0xFF607D8B)], // 浅色模式：灰蓝色
+    );
+  }
+
+  // 雨天 - 深蓝色
+  if (weatherType.contains('雨') ||
+      ['阵雨', '雷阵雨', '小雨', '中雨', '大雨', '暴雨']
+          .any((rain) => weatherType.contains(rain))) {
+    return LinearGradient(
+      begin: Alignment.topLeft,
+      end: Alignment.bottomRight,
+      colors: isDarkMode
+          ? [Color(0xFF1565C0), Color(0xFF0D47A1)] // 深色模式：深蓝色
+          : [Color(0xFF42A5F5), Color(0xFF1976D2)], // 浅色模式：亮蓝色
+    );
+  }
+
+  // 雪天 - 冷色调蓝白色
+  if (weatherType.contains('雪') ||
+      ['阵雪', '小雪', '中雪', '大雪', '暴雪']
+          .any((snow) => weatherType.contains(snow))) {
+    return LinearGradient(
+      begin: Alignment.topLeft,
+      end: Alignment.bottomRight,
+      colors: isDarkMode
+          ? [Color(0xFF0277BD), Color(0xFF01579B)] // 深色模式：深冷蓝
+          : [Color(0xFF81D4FA), Color(0xFF29B6F6)], // 浅色模式：浅蓝色
+    );
+  }
+
+  // 雾霾天 - 暗黄灰色
+  if (weatherType.contains('雾') ||
+      weatherType.contains('霾') ||
+      ['雾', '浓雾', '霾', '中度霾', '重度霾'].any((fog) => weatherType.contains(fog))) {
+    return LinearGradient(
+      begin: Alignment.topLeft,
+      end: Alignment.bottomRight,
+      colors: isDarkMode
+          ? [Color(0xFF5D4037), Color(0xFF3E2723)] // 深色模式：深棕色
+          : [Color(0xFF8D6E63), Color(0xFF6D4C41)], // 浅色模式：棕灰色
+    );
+  }
+
+  // 大风天 - 青绿色
+  if (weatherType.contains('风') ||
+      ['大风', '强风', '疾风', '烈风'].any((wind) => weatherType.contains(wind))) {
+    return LinearGradient(
+      begin: Alignment.topLeft,
+      end: Alignment.bottomRight,
+      colors: isDarkMode
+          ? [Color(0xFF00695C), Color(0xFF004D40)] // 深色模式：深青色
+          : [Color(0xFF26A69A), Color(0xFF00796B)], // 浅色模式：青绿色
+    );
+  }
+
+  // 默认 - 原来的蓝色
+  return LinearGradient(
+    begin: Alignment.topLeft,
+    end: Alignment.bottomRight,
+    colors: isDarkMode
+        ? [Color(0xFF1E40AF), Color(0xFF1E3A8A)]
+        : [Color(0xFF60A5FA), Color(0xFF3B82F6)],
+  );
+}