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Summary

• Retry retryable failures while establishing and using Flight do_exchange streams
• Keep receiver session state across reconnects and use sequence acknowledgements to deduplicate replayed DATA frames
• Add explicit FINISH/FINISH_ACK frames and distinguish receiver-driven completion, such as LIMIT, from network failures
• Encapsulate the wire protocol in DoExchangeFrame; query nodes are expected to run the same version

Next PR: migrate do_get to do_exchange

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

This change is