fix(gfql): preserve open-range bindings serialization (#880) - #1016

Summary

Fix the native GFQL bindings-table serialization bug that was collapsing open-range/fixed-point edge segments back to a single hop during rows() / rows(binding_ops=...) replay.

What changed

• normalize edge JSON serialization so range/fixed-point segments do not emit the constructor default hops=1
• add native GFQL regressions for the IS6-style multihop continuation shape in both bare rows() and direct rows(binding_ops=...)
• add benchmark-shaped Cypher regressions for IS1 / IS3 / IS6 shapes that currently work on master
• add a Development changelog entry

Scope note

This clears the confirmed residual #880 multihop bindings bug behind IS6-style native/workaround paths.
IS7 remains the separate #996 OPTIONAL MATCH lane; this PR does not claim to solve it.

Verification

• python3.12 -B -m pytest -q graphistry/tests/compute/test_ast.py graphistry/tests/test_compute_chain.py -k "open_range or ChainBindingsTable"
• python3.12 -B -m pytest -q graphistry/tests/compute/gfql/cypher/test_lowering.py -k "is1_seed_city_projection_shape or is3_seed_expand_projection_shape or is6_open_range_continuation_projection_shape"