feat(Core/Database): move MySQL handle and HandleMySQLErrno to protected (#14673)

* feat(Core/Database): move MySQL handle and HandleMySQLErrno to protected

* fix: initialization order

src/server/database/Database/MySQLConnection.h

@@ -98,19 +98,18 @@ protected:
     void PrepareStatement(uint32 index, std::string_view sql, ConnectionFlags flags);
 
     virtual void DoPrepareStatements() = 0;
+    virtual bool _HandleMySQLErrno(uint32 errNo, uint8 attempts = 5);
 
     typedef std::vector<std::unique_ptr<MySQLPreparedStatement>> PreparedStatementContainer;
 
     PreparedStatementContainer m_stmts; //! PreparedStatements storage
     bool m_reconnecting;  //! Are we reconnecting?
     bool m_prepareError;  //! Was there any error while preparing statements?
+    MySQLHandle* m_Mysql; //! MySQL Handle.
 
 private:
-    bool _HandleMySQLErrno(uint32 errNo, uint8 attempts = 5);
-
     ProducerConsumerQueue<SQLOperation*>* m_queue;      //! Queue shared with other asynchronous connections.
     std::unique_ptr<DatabaseWorker> m_worker;           //! Core worker task.
-    MySQLHandle* m_Mysql;                               //! MySQL Handle.
     MySQLConnectionInfo& m_connectionInfo;              //! Connection info (used for logging)
     ConnectionFlags m_connectionFlags;                  //! Connection flags (for preparing relevant statements)
     std::mutex m_Mutex;