docs: improve GitHub discovery badges

[phantom5125]

Summary

• add clickable badges for the native Mac app, five coding plans, C152/ESP32-S3, BLE protocol, privacy, releases, stars, CI, and licensing
• clarify in English and Chinese that TokenLink runs fully on the Mac without a watch, while C152 adds an optional ambient display and interaction surface
• reposition the project as a Mac-first coding-plan control plane with an optional wrist companion

The GitHub repository description and Topics were also updated through repository settings to improve discovery across Codex, Claude Code, macOS menu-bar, M5Stack, ESP32-S3, and token-usage searches.

Validation

• git diff --check
• both READMEs rendered successfully through the GitHub Markdown API
• all badge image endpoints returned HTTP 200