refactor(cpp): 更新CMake配置和异常处理逻辑

[TsinghuaDream]

• 替换默认CMake模板为更现代的CMakeLists.modern.txt配置
• 新增和优化多个测试和示例项目的CMakeLists文件
• 修改异常捕获从Darabonba::Exception到std::exception和Darabonba::DaraException
• 调整抛出异常逻辑，使用Darabonba::UnretryableException封装异常上下文
• 清理未使用的异常成员变量声明
• 新增CMake代码覆盖率支持脚本和测试配置
• 调整导入依赖逻辑，改进darabonba_core库的获取和使用机制

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