v4.0.0

Highlights

• Upgrade to DataFusion 55: bumps a major version in the DataFusion dependency

Upgrade notes

See the 4.0.0 upgrade guide for migrations from 3.0.0.

What's Changed

• Update doc by @gabotechs in #644
• Small doc fix by @gabotechs in #645
• Tweak AI review policy by @gabotechs in #654
• Remove ColaescePartitionsExec special-case by @gabotechs in #655
• Optional serialization/deserialization for WorkerChannel by @gabotechs in #566
• Add in-process worker implementation by @gabotechs in #656
• upgrade to datafusion 55 by @jayshrivastava in #540

Full Changelog: v3.0.0...v4.0.0