The self-hosted Windows runner can't reach github.com (GFW), so the previous
workflow failed cloning actions/checkout and would also fail downloading the
Flutter SDK and the sqlite3 native binary.
- Vendor the official, SHA-256-verified sqlite3 binaries under vendor/sqlite3/
and select them via pubspec hooks.user_defines (source: test-sqlite3). Builds
and tests now run fully offline — no GitHub download, no proxy, no
LD_LIBRARY_PATH hack (removed .local-sqlite/).
- Consolidate CI into one Windows workflow: fetch actions from the gitea.com
mirror, use the runner's pre-installed Flutter (no SDK download), and use the
flutter-io.cn pub/Flutter mirrors. Server tests use the Tsinghua PyPI mirror.
- Document the offline build + China mirrors in README.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
