- Add CODEWHALE_RELEASE_BASE_URL as canonical env override for release
asset base URL (DEEPSEEK_TUI_RELEASE_BASE_URL and DEEPSEEK_RELEASE_BASE_URL
remain as legacy fallbacks).
- Add CODEWHALE_USE_CNB_MIRROR env var to auto-select the CNB (cnb.cool)
mirror for binary downloads, avoiding GitHub Releases timeouts in China.
- Update npm install scripts (artifacts.js) with the same env checks.
- Update Rust self-updater (update.rs) with new constants and env cascade.
Fixes#2222.
Hunter Bown
0706285bfe