Add bilingual README and reproducible setup flow

[xymeow]

Summary

• remove current-tree references to a private predecessor repository while preserving this public project's market-watching functionality
• add mirrored English and Simplified Chinese README and host documentation
• add dedicated How to Use / 使用方法 and troubleshooting sections for head touch, QR setup, watcher acknowledgement, standalone markets, and TTS
• make installation reproducible by pinning the tested upstream Stack-chan commit, separating required and optional patches, fixing working-directory assumptions, and documenting placeholder tickers
• add an imagegen-created system architecture diagram with the actual phone, watcher, device, and TTS data flow
• enable the setup service in the example configuration and render generated QR assets using their natural texture dimensions

Why

The existing README exposed private-project history and mixed old/new setup assumptions. Following it from a clean checkout could fail because commands changed repositories without resetting the working directory, the optional font patch was applied by a wildcard, the example tickers were not live, setup was disabled by default, and regenerated QR images did not match a hard-coded texture region.

Impact

New users get a bilingual, end-to-end installation and usage path. Device QR assets can use their generated dimensions, and the primary phone setup flow works from the copied example configuration. Trading and account-access behavior remains unchanged: the project is still read-only.

Checks

• python3 -m unittest discover -s tools -p 'test_*.py' — 91 tests passed
• ESM syntax check for every mod/*.js
• JSON parsing for all four JSON files
• staged diff whitespace check
• local Markdown link check
• both host patches apply cleanly to ded5ca94ef50411aec213b85a23d1afe72d4c29e
• current-tree search returns no private repository name or URL

[xymeow]

modified readme