Add release packaging and project docs

[jayvenn21]

Summary

• Add macOS/Linux release packaging through GitHub Actions
• Add a local release packaging script for reviewable binary archives
• Add developer, user, and distribution documentation
• Link the new docs from the README

Details

This adds a release workflow that builds and tests platform binaries for Linux and macOS, packages the binary with examples and docs, and publishes artifacts to GitHub Releases when a v* tag is pushed.

The new docs cover:

• repository structure and architecture
• metadata registry and connector model
• adding new table-backed datasets
• local build/test instructions
• install, materialize, FUSE, and NFS usage
• known limitations
• release checklist

Validation

• cargo fmt -- --check
• cargo test --locked
• ./scripts/package-release.sh
• Sample materialization smoke test with the release binary

[jayvenn21]

Closing in favor of the consolidated final GSoC submission PR: #4