Package release artifacts and document Cassandra-node deployment

[hshimizu]

Parent: #1

Summary

Make the version-specific thin JARs releasable and operable on Cassandra nodes without repackaging Cassandra itself.

Implementation plan

• Publish one clearly named artifact per supported release line.
• Generate checksums, signatures, SBOMs, dependency/license notices, and reproducible build metadata.
• Verify release artifacts contain no Cassandra server classes or runtime JARs.
• Document:
  • tarball, Debian, and RPM-style Cassandra layouts;
  • required Cassandra and Java patch ranges;
  • --cassandra-home/--cassandra-conf/--java-home;
  • workspace placement and disk sizing;
  • snapshot/backup input requirements;
  • loopback ports and cqlsh connection;
  • delta/snapshot export and supported production import procedures;
  • crash recovery and cleanup;
  • classpath/linkage troubleshooting.
• Provide a preflight-only command suitable for deployment automation.
• Provide a release compatibility manifest consumable by the bootstrap.
• Make warnings explicit that the tool never targets the live Cassandra JVM/data directory.

Acceptance criteria

• A release can be installed and removed without modifying Cassandra's installation.
• Following the node deployment guide produces a working workspace on every supported release line.
• Preflight detects all required runtime/configuration errors before opening SSTables.
• Artifacts are checksummed, signed, and accompanied by SBOM/license data.
• The published compatibility matrix is generated from passing contract tests.
• Upgrade and rollback procedures for the tool JAR do not affect Cassandra.

Dependencies

Depends on #2, #3, #8, #9, #10, and #11.

Design

See sections 7.2, 7.3, 14, and 19 of docs/cql-mutation-workspace-design.md.

[hshimizu]

Commits 953ea5e and 587a213 make release bundle contents match the requested release version and add CI verification for both snapshot and versioned bundles. The verifier checks manifest-to-artifact mapping, SHA-256 checksums, required SBOM/notices, and rejects packaged Cassandra classes. CI run 30261383898 passed. Issue remains open for release signing and final deployment workflow evidence.