docs: expand README.md into detailed Chinese user guide

[2228293026]

Motivation

• Improve user onboarding by providing a full Chinese guide that explains features, modes, and common pitfalls.
• Make configuration discoverable by mapping UI settings to concrete examples and usage scenarios.
• Help advanced users and developers with build instructions and a clear project layout.

Description

• Replaced the short README.md with an expanded Chinese documentation containing a TOC and 10 sections covering feature overview, working modes, installation & updates, developer build notes, and project structure.
• Added a detailed settings table and examples that map UI options (e.g. Macro, MacroKeys, SimulateKeyPress, SkyHookMode, InputMode, EnableKeyFilter, FilteredKeys) to expected behavior.
• Included runtime tuning tips, recommended presets for common scenarios, and a troubleshooting FAQ to speed up issue resolution.
• This is documentation-only and does not change runtime code or behavior.

Testing

• Performed a whitespace/format check of the patch and found no formatting issues.
• Verified the new README.md renders as plain Markdown without structural errors by previewing the file content.
• No runtime or unit tests were required because this change is documentation-only.

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Codex Task