refactor: 大规模调整项目目录结构，将ChatClient和ChatServer整合为Monorepo结构，并分为两个独立文件夹：chatclient/ 和 chatserver/。更新了ChatClient的CMakeLists.txt配置以适配新结构。

ChatClient/include/choosefrienddialog.h

@@ -0,0 +1,72 @@
+#pragma once
+
+#include <QDialog>
+#include <QWidget>
+#include <QHBoxLayout>
+#include <QScrollArea>
+#include <QScrollBar>
+#include <QPushButton>
+#include <QPainter>
+#include <QCheckBox>
+#include <QLabel>
+
+#include "debug.h"
+
+class ChooseFriendDialog;
+
+////////////////////////////////////////////////
+/// 选择好友窗口中的一个 元素/好友项
+////////////////////////////////////////////////
+class ChooseFriendItem : public QWidget {
+	Q_OBJECT
+public:
+	ChooseFriendItem(ChooseFriendDialog* owner, const QString& userId, const QIcon& avatar, const QString& name, bool checked);
+
+	void paintEvent(QPaintEvent* event) override;
+	void enterEvent(QEnterEvent* event) override;
+	void leaveEvent(QEvent* event) override;
+
+	QString& getUserId() {
+		return userId;
+	}
+
+	QCheckBox* getCheckBox() {
+		return checkBox;
+	}
+
+private:
+	bool isHover = false;
+
+	QCheckBox* checkBox;
+	QPushButton* avatarBtn;
+	QLabel* nameLabel;
+	ChooseFriendDialog* owner; //记录了哪个QWidget持有这个Item，此处应该是ChooseFriendDialog
+
+	QString userId; //记录成员id用于删除唯一指定的成员Item
+};
+
+class ChooseFriendDialog  : public QDialog
+{
+	Q_OBJECT
+
+public:
+	ChooseFriendDialog(QWidget *parent, const QString& userId);
+
+	void initLeft(QHBoxLayout* layout);
+	void initRight(QHBoxLayout* layout);
+	void initData();
+
+	void addFriend(const QString& userId, const QIcon& avatar, const QString& name, bool checked);
+	void addSelectedFriend(const QString& userId, const QIcon& avatar, const QString& name);
+	void deleteSelectedFriend(const QString& userId);
+
+	void clickOkBtn();
+	QList<QString> generateMemberList();
+private:
+	QWidget* totalContainer;
+	QWidget* selectedContainer;
+
+	//当前选择窗口是点击哪个用户弹出的
+	QString userId;
+};
+