fix(cypher): admit IC11 person!=friend scope through reentry prefix (#1391) - #1401

Summary

Fixes the IC11/job-referral residual blocker tracked by #1391 by admitting the prefix-stage WHERE NOT(person=friend) scope in the reentry compilation path.

What changed

• graphistry/compute/gfql/cypher/lowering.py
  • Preserve pre-scope binding aliases for MATCH-row WHERE validation in _lower_projection_chain.
  • Use the union of scoped aliases + pre-scope aliases when validating row WHERE expressions.
  • Keep bindings-row routing enabled when pre-scope aliases are required for WHERE.
• graphistry/tests/compute/gfql/cypher/test_lowering.py
  • Added IC11-shaped regression test covering:
    • MATCH (person)-[:KNOWS*1..2]-(friend)
    • WHERE NOT(person=friend)
    • WITH DISTINCT friend
    • trailing employment/company/country join and ordering
  • Added cuDF parity test for the same shape.

Why

#1391 tracks an employment/company row-join residual lane (interactive-complex-11 / job-referral) that still required adapter-side join workaround logic. The row join path itself already executed; the prefix compile path rejected NOT(person=friend) after scope trimming. This patch fixes that admission gap.

Validation

• python -m pytest -q graphistry/tests/compute/gfql/cypher/test_lowering.py -k "job_referral_employment_company_row_join_shape"
• python -m pytest -q graphistry/tests/compute/gfql/cypher/test_lowering.py -k "seeded_multihop_then_with_match_reentry_shape or seeded_multihop_then_with_optional_match_reentry_shape"
• uv run ruff check graphistry/compute/gfql/cypher/lowering.py graphistry/tests/compute/gfql/cypher/test_lowering.py

Issue linkage

• Fixes [FEA] GFQL residual row-bindings: employment company row join #1391
• Umbrella: [FEA] GFQL bindings_table (row bindings) from chain using Yannakakis prune #880