feat: 添加依赖自动检测与安装、选项记忆、KDocs登录优化

- 新增依赖检测模块：启动时自动检测wkhtmltoimage和Playwright Chromium
- 新增依赖安装对话框：缺失时提示用户一键下载安装
- 修复选项记忆功能：浏览类型、自动截图、自动上传选项现在会保存
- 优化KDocs登录检测：未登录时自动切换到金山文档页面并显示二维码
- 简化日志输出：移除debug信息，保留用户友好的状态提示
- 新增账号变化信号：账号管理页面的修改会自动同步到浏览任务页面

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

config.py

@@ -79,6 +79,14 @@ class ZSGLConfig:
     index_url_pattern: str = "index.aspx"
 
 
+@dataclass
+class TaskConfig:
+    """浏览任务配置"""
+    browse_type: str = "应读"  # 浏览类型
+    auto_screenshot: bool = True  # 浏览后自动截图
+    auto_upload: bool = False  # 截图后自动上传
+
+
 @dataclass
 class AppConfig:
     """应用总配置"""
@@ -87,6 +95,7 @@ class AppConfig:
     screenshot: ScreenshotConfig = field(default_factory=ScreenshotConfig)
     proxy: ProxyConfig = field(default_factory=ProxyConfig)
     zsgl: ZSGLConfig = field(default_factory=ZSGLConfig)
+    task: TaskConfig = field(default_factory=TaskConfig)
     theme: str = "light"  # light/dark
 
     def to_dict(self) -> dict:
@@ -130,6 +139,11 @@ class AppConfig:
                 "login_url": self.zsgl.login_url,
                 "index_url_pattern": self.zsgl.index_url_pattern,
             },
+            "task": {
+                "browse_type": self.task.browse_type,
+                "auto_screenshot": self.task.auto_screenshot,
+                "auto_upload": self.task.auto_upload,
+            },
             "theme": self.theme,
         }
 
@@ -191,6 +205,14 @@ class AppConfig:
             index_url_pattern=zsgl_data.get("index_url_pattern", "index.aspx"),
         )
 
+        # 加载任务配置
+        task_data = data.get("task", {})
+        config.task = TaskConfig(
+            browse_type=task_data.get("browse_type", "应读"),
+            auto_screenshot=task_data.get("auto_screenshot", True),
+            auto_upload=task_data.get("auto_upload", False),
+        )
+
         # 主题
         config.theme = data.get("theme", "light")