feat(core): 优化下载管理器和进度窗口

- 在下载管理器中引入 CloudflareOptimizer、DownloadTaskManager 和 ExtractionHandler 模块，重构下载流程
- 优化下载进度更新频率，减少 UI 卡顿
- 改进下载和解压缩的处理逻辑，确保更流畅的用户体验
- 更新下载线程设置，支持更灵活的下载管理

source/core/download_task_manager.py

@@ -0,0 +1,221 @@
+from PySide6 import QtWidgets
+from PySide6.QtCore import Qt
+from PySide6.QtWidgets import QDialog, QVBoxLayout, QRadioButton, QPushButton, QLabel, QButtonGroup, QHBoxLayout
+from PySide6.QtGui import QFont
+
+from data.config import DOWNLOAD_THREADS
+
+
+class DownloadTaskManager:
+    """下载任务管理器，负责管理下载任务和线程设置"""
+    
+    def __init__(self, main_window, download_thread_level="medium"):
+        """初始化下载任务管理器
+        
+        Args:
+            main_window: 主窗口实例，用于访问UI和状态
+            download_thread_level: 下载线程级别，默认为"medium"
+        """
+        self.main_window = main_window
+        self.APP_NAME = main_window.APP_NAME if hasattr(main_window, 'APP_NAME') else ""
+        self.current_download_thread = None
+        self.download_thread_level = download_thread_level
+    
+    def start_download(self, url, _7z_path, game_version, game_folder, plugin_path):
+        """启动下载线程
+        
+        Args:
+            url: 下载URL
+            _7z_path: 7z文件保存路径
+            game_version: 游戏版本名称
+            game_folder: 游戏文件夹路径
+            plugin_path: 插件路径
+        """
+        # 按钮在file_dialog中已设置为禁用状态
+        
+        # 创建并连接下载线程
+        self.current_download_thread = self.main_window.create_download_thread(url, _7z_path, game_version)
+        self.current_download_thread.progress.connect(self.main_window.progress_window.update_progress)
+        self.current_download_thread.finished.connect(
+            lambda success, error: self.main_window.download_manager.on_download_finished(
+                success,
+                error,
+                url,
+                game_folder,
+                game_version,
+                _7z_path,
+                plugin_path,
+            )
+        )
+        
+        # 连接停止按钮到download_manager的on_download_stopped方法
+        self.main_window.progress_window.stop_button.clicked.connect(self.main_window.download_manager.on_download_stopped)
+        
+        # 连接暂停/恢复按钮
+        self.main_window.progress_window.pause_resume_button.clicked.connect(self.toggle_download_pause)
+        
+        # 启动线程和显示进度窗口
+        self.current_download_thread.start()
+        self.main_window.progress_window.exec()
+
+    def toggle_download_pause(self):
+        """切换下载的暂停/恢复状态"""
+        if not self.current_download_thread:
+            return
+            
+        # 获取当前暂停状态
+        is_paused = self.current_download_thread.is_paused()
+        
+        if is_paused:
+            # 如果已暂停，则恢复下载
+            success = self.current_download_thread.resume()
+            if success:
+                self.main_window.progress_window.update_pause_button_state(False)
+        else:
+            # 如果未暂停，则暂停下载
+            success = self.current_download_thread.pause()
+            if success:
+                self.main_window.progress_window.update_pause_button_state(True)
+    
+    def get_download_thread_count(self):
+        """获取当前下载线程设置对应的线程数
+        
+        Returns:
+            int: 下载线程数
+        """
+        # 获取当前线程级别对应的线程数
+        thread_count = DOWNLOAD_THREADS.get(self.download_thread_level, DOWNLOAD_THREADS["medium"])
+        return thread_count
+        
+    def set_download_thread_level(self, level):
+        """设置下载线程级别
+        
+        Args:
+            level: 线程级别 (low, medium, high, extreme, insane)
+            
+        Returns:
+            bool: 设置是否成功
+        """
+        if level in DOWNLOAD_THREADS:
+            old_level = self.download_thread_level
+            self.download_thread_level = level
+            
+            # 只有非极端级别才保存到配置
+            if level not in ["extreme", "insane"]:
+                if hasattr(self.main_window, 'config'):
+                    self.main_window.config["download_thread_level"] = level
+                    self.main_window.save_config(self.main_window.config)
+                    
+            return True
+        return False
+    
+    def show_download_thread_settings(self):
+        """显示下载线程设置对话框"""
+        # 创建对话框
+        dialog = QDialog(self.main_window)
+        dialog.setWindowTitle(f"下载线程设置 - {self.APP_NAME}")
+        dialog.setMinimumWidth(350)
+        
+        layout = QVBoxLayout(dialog)
+        
+        # 添加说明标签
+        info_label = QLabel("选择下载线程数量（更多线程通常可以提高下载速度）：", dialog)
+        info_label.setWordWrap(True)
+        layout.addWidget(info_label)
+        
+        # 创建按钮组
+        button_group = QButtonGroup(dialog)
+        
+        # 添加线程选项
+        thread_options = {
+            "low": f"低速 - {DOWNLOAD_THREADS['low']}线程（慢慢来，不着急）",
+            "medium": f"中速 - {DOWNLOAD_THREADS['medium']}线程（快人半步）",
+            "high": f"高速 - {DOWNLOAD_THREADS['high']}线程（默认，推荐配置）",
+            "extreme": f"极速 - {DOWNLOAD_THREADS['extreme']}线程（如果你对你的网和电脑很自信的话）",
+            "insane": f"狂暴 - {DOWNLOAD_THREADS['insane']}线程（看看是带宽和性能先榨干还是牛牛先榨干）"
+        }
+        
+        radio_buttons = {}
+        
+        for level, text in thread_options.items():
+            radio = QRadioButton(text, dialog)
+            
+            # 选中当前使用的线程级别
+            if level == self.download_thread_level:
+                radio.setChecked(True)
+                
+            button_group.addButton(radio)
+            layout.addWidget(radio)
+            radio_buttons[level] = radio
+            
+        layout.addSpacing(10)
+        
+        # 添加按钮区域
+        btn_layout = QHBoxLayout()
+        
+        ok_button = QPushButton("确定", dialog)
+        cancel_button = QPushButton("取消", dialog)
+        
+        btn_layout.addWidget(ok_button)
+        btn_layout.addWidget(cancel_button)
+        
+        layout.addLayout(btn_layout)
+        
+        # 连接按钮事件
+        ok_button.clicked.connect(dialog.accept)
+        cancel_button.clicked.connect(dialog.reject)
+        
+        # 显示对话框
+        result = dialog.exec()
+        
+        # 处理结果
+        if result == QDialog.DialogCode.Accepted:
+            # 获取用户选择的线程级别
+            selected_level = None
+            for level, radio in radio_buttons.items():
+                if radio.isChecked():
+                    selected_level = level
+                    break
+                    
+            if selected_level:
+                # 为极速和狂暴模式显示警告
+                if selected_level in ["extreme", "insane"]:
+                    warning_result = QtWidgets.QMessageBox.warning(
+                        self.main_window,
+                        f"高风险警告 - {self.APP_NAME}",
+                        "警告！过高的线程数可能导致CPU负载过高或其他恶性问题！\n你确定要这么做吗？",
+                        QtWidgets.QMessageBox.StandardButton.Yes | QtWidgets.QMessageBox.StandardButton.No,
+                        QtWidgets.QMessageBox.StandardButton.No
+                    )
+                    
+                    if warning_result != QtWidgets.QMessageBox.StandardButton.Yes:
+                        return False
+                
+                success = self.set_download_thread_level(selected_level)
+                
+                if success:
+                    # 显示设置成功消息
+                    thread_count = DOWNLOAD_THREADS[selected_level]
+                    message = f"\n已成功设置下载线程为: {thread_count}线程\n"
+                    
+                    # 对于极速和狂暴模式，添加仅本次生效的提示
+                    if selected_level in ["extreme", "insane"]:
+                        message += "\n注意：极速/狂暴模式仅本次生效。软件重启后将恢复默认设置。\n"
+                    
+                    QtWidgets.QMessageBox.information(
+                        self.main_window,
+                        f"设置成功 - {self.APP_NAME}",
+                        message
+                    )
+                
+            return True
+            
+        return False 
+    
+    def stop_download(self):
+        """停止当前下载线程"""
+        if self.current_download_thread and self.current_download_thread.isRunning():
+            self.current_download_thread.stop()
+            self.current_download_thread.wait()  # 等待线程完全终止
+            return True
+        return False