v0.2.1 — Fix Linux/Windows install

Fixed

• npm install failed on Linux and Windows because sqlite-vec-darwin-arm64 was incorrectly declared as a regular dependencies entry in package.json. npm treated it as a hard, cross-platform requirement and bailed with EBADPLATFORM on non-macOS-arm64 hosts (including the GitHub Actions Ubuntu runner). The sqlite-vec package already declares all platform binaries as optionalDependencies and resolves the right one per host, so the explicit hard dep was both redundant and wrong. Removed; lockfile regenerated.

Users on 0.2.0 should upgrade to 0.2.1 if installing on Linux, Windows, or macOS x64. macOS arm64 installs were unaffected.