新增 DfPlayer 和 CanMv 类，优化 UART 读写方法，更新 CommonCenter 以支持新类实例化

Core/App/Center/common_center.hpp

@@ -1,5 +1,7 @@
 #pragma once
 
+#include "../Common/can_mv.hpp"
+#include "../Common/df_player.hpp"
 #include "../Common/ultrasonic.hpp"
 #include "../config.hpp"
 
@@ -13,4 +15,20 @@ public:
         }
         return *instance;
     }
+
+    static DfPlayer& GetDfPlayer() {
+        static DfPlayer* instance = nullptr;
+        if (instance == nullptr) {
+            instance = new DfPlayer(Config::kDfPlayerUart);
+        }
+        return *instance;
+    }
+
+    static CanMv& GetCanMv() {
+        static CanMv* instance = nullptr;
+        if (instance == nullptr) {
+            instance = new CanMv(Config::kCanMvUart);
+        }
+        return *instance;
+    }
 };