fix(gfql): recursive ancestor row-join duplicate carry fallback (#1394) - #1403

Summary

• fix recursive/repeated-primary whole-row reentry for duplicate carried ids with scalar carries
• keep low-level duplicate-carried-row guard in reentry execution, but add structured fallback in gfql_unified to run suffix per prefix row and union results
• add structured error context key for duplicate-carried-row detection and route without brittle message matching
• convert prior failfast lock into success lock for bag-semantics behavior in chained reentry
• add changelog entry for [FEA] GFQL residual row-bindings: recursive ancestor row join #1394

Validation

• python -m pytest -q graphistry/tests/compute/gfql/cypher/test_lowering.py -k "chained_reentry_with_repeated_primary_preserves_prefix_row_bag_semantics"
• python -m pytest -q graphistry/tests/compute/test_gfql.py -k "reentry_state_rejects_invalid_carried_scalar_rows"
• python -m pytest -q graphistry/tests/compute/gfql/cypher/test_lowering.py -k "reentry"
• ./bin/ruff.sh graphistry/compute/gfql_unified.py graphistry/compute/gfql/cypher/reentry/execution.py graphistry/tests/compute/gfql/cypher/test_lowering.py

Closes #1394