[beinan]

The v0.6.7 Rust release failed when crates.io rejected lance-context-metrics 0.1.0 with missing or empty metadata fields: description. Add the missing description and validate the required registry metadata for every publishable workspace crate before packaging or publishing. The check ignores publish = false crates and runs on manifest changes as well as workflow changes.

cargo package --no-verify only warns about missing metadata, so the existing PR validation did not catch this upload failure. The new check fails before any crate is uploaded.

Validation:

• The new metadata check reproduces the failure before the manifest fix and passes afterward.
• cargo package --workspace --exclude lance-context-python --allow-dirty --no-verify --all-features --locked passes.
• cargo publish -p lance-context-metrics --dry-run --allow-dirty --locked passes, including compilation of the packaged crate.
• Actionlint, Ruff lint/format for the embedded Python, and git diff --check pass.

After merging, retry Rust publishing with workflow_dispatch on main and mode=release. Re-running the failed tag-based run would still use the old manifest.

Failed release: https://github.com/lance-format/lance-context/actions/runs/35279364852