v0.5.0

Highlights

• Implement cooperative shard handoff for consumer-group rebalancing.
• Preserve parent/child shard ordering so child shards wait for parent completion.
• Release consumer-group shards cleanly on graceful shutdown.
• Improve throttling retry handling and buffered checkpoint flushing.

Breaking Change

• Remove the lease-stealing API introduced during the consumer-group work. This release is cut as v0.5.0 instead of a patch release because that public API surface was removed.

Included Changes

• Fix buffered checkpoint flushing on scan exit (#189)
• Flush checkpoints before lease release (#190)
• Document aggregation checkpoint limits (#191)
• Remove lease stealing API (#192)
• Improve throttling retry handling (#194)
• Gate child shards on parent completion (#193)
• Implement cooperative shard handoff for consumer-group rebalancing (#196)
• Document consumer-group handoff changes
• Release group shards on graceful shutdown
• Add shutdown and handoff end-to-end coverage
• Fix root package shutdown test coverage