v0.1.0 - distribution channels

First release carrying the full distribution-channels work (issue #6), published
end-to-end from the feat/distribution-channels branch:

• Runtime-agnostic core plus a browser entry (@libredb/libredb/browser).
• Published to JSR (@libredb/libredb) alongside npm.
• CLI libredb (npx libredb): inspect, stats, get, scan, set, delete, import.
• Standalone binaries for Linux, macOS, and Windows (x64 + arm64) attached below,
  each with a .sha256 checksum.
• Multi-arch Docker image at ghcr.io/libredb/libredb.
• OPFS-backed browser persistence via opfsFileSystem.