[WIP] Optimize code for better performance

[Copilot]

Performance optimization plan:

• Remove unnecessary async sleep operations in services.py
• Optimize DataManager save operations - batch saves where possible
• Optimize list operations and avoid unnecessary copies
• Reduce redundant page.update() calls in UI
• Optimize pick_weighted algorithm to avoid list rebuilding
• Cache statistics calculations where appropriate
• Optimize file I/O operations
• Run code review and security checks

Original prompt

优化代码性能

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