Improve README with bilingual documentation and dependency management

[Copilot]

README lacked English translation, structured installation guide, and dependency management. Added comprehensive documentation improvements.

Changes

• Bilingual support: Added complete English translation with navigation anchors
• Dependency management: Created requirements.txt with versioned dependencies (longport, matplotlib, pynput)
• Prerequisites section: Python 3.7+, network, Longbridge account
• Installation guide: Added repo cloning, two installation methods (requirements.txt vs manual), explicit API credential configuration
• Troubleshooting: Documented 4 common failure modes (API connection, file permissions, keyboard listener, chart updates)
• Known issues: Documented position tracking display bug from code comments
• Project structure: Updated to reflect all files including new requirements.txt

Example

Installation now provides clear credential setup:

config = Config(
    app_key="your_app_key_here",       # Replace with your APP Key
    app_secret="your_app_secret_here", # Replace with your APP Secret
    access_token="your_access_token"   # Replace with your Access Token
)

No code changes, documentation only.

Original prompt

完善readme

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