描述 本PR引入了多项稳定性改进和兼容性增强：

1. Python 3.8+ 兼容性：

   • 在 、 和 中重构型提示（用 和 替换）。X | Y``Union[X, Y]``Optional[X]``backend/app.py``scripts/smoke_test.py``webp_to_spritesheet.py
   • 更新了README（EN/CN/JP），以反映较低的Python要求（3.8+，而非3.10+）。

2. 内存泄漏修复：

   • 该功能实现了自动移除超过1小时的陈旧背景任务。_cleanup_bg_tasks``backend/app.py

3. 代理推送脚本优化：

   • 移除了硬编码路径，以便更好地跨平台支持。/root/``office-agent-push.py
   • 增加了彩色日志以提升用户体验。
   • 同步更改到 .frontend/office-agent-push.py

4. **维护：

   • 已更新，排除了IDE配置（、）和临时文件。.gitignore``.vscode``.idea

   变更类型

• 漏洞修复（非破坏性修改，修复了某个问题）
• 重构（不做功能变更，不做 API 变更）
• 文档更新

Description
This PR introduces a comprehensive set of improvements focusing on stability, cross-platform compatibility, and community growth.

Key Changes:

1. Python 3.8+ Compatibility:

   • Refactored type hints (replaced X | Y with Union[X, Y] and Optional[X]) in backend/app.py, scripts/smoke_test.py, and webp_to_spritesheet.py.
   • Updated READMEs (CN/EN/JP) to reflect the broader environment support.

2. Stability & Performance:

   • Added _cleanup_bg_tasks in backend/app.py to auto-remove stale background tasks older than 1 hour, preventing potential memory leaks.
   • Added detailed debugging logs to the /agent-push endpoint for easier troubleshooting.

3. Cross-Platform & Path Cleanup:

   • Removed hardcoded /root/ and user-specific absolute paths in:
     • resize_map.py (added argparse support)
     • repack_star_working.py
     • convert_to_webp.py
     • healthcheck.sh
   • Scripts now dynamically resolve paths or accept command-line arguments.

4. Agent Push Script Enhancement:

   • Re-designed office-agent-push.py with colored logging and robust automatic path discovery for state.json.

5. Community & Documentation:

   • Added a "Contributing" section to READMEs in all three languages to guide new contributors.
   • Refined .gitignore to exclude IDE-specific configurations.

   Type of change

• Bug fix (non-breaking change which fixes an issue)
• Refactoring (performance/stability improvement, no functional changes)
• Documentation update