Fix GFQL schema validation and ref traversal

[lmeyerov]

Summary

• validate boundary call mixing before schema validation and propagate call schema effects
• restore ASTRef edge traversals to use original graph + start nodes
• relax bool type mismatch checks in schema/filter validation
• align enrichment/call schema tests and update changelog

Testing

• uv run env PYTHONPATH=. pytest graphistry/tests/compute/test_astcall_topology.py::TestEnrichmentChains::test_enrichment_degree_then_filter graphistry/tests/compute/test_astcall_topology.py::TestEnrichmentChains::test_enrichment_multiple_degrees graphistry/tests/compute/test_astcall_topology.py::TestEnrichmentChains::test_enrichment_before_traversal graphistry/tests/compute/test_call_schema_validation.py::TestCallSchemaValidation::test_chain_with_multiple_calls graphistry/tests/compute/test_id_column_restriction.py::TestProblematicColumnNames::test_let_ref_with_problematic_columns -q
• uv run env PYTHONPATH=. pytest graphistry/tests/compute/test_astcall_topology.py::TestEnrichmentChains::test_enrichment_filter_enrichment_filter graphistry/tests/compute/test_astcall_topology.py::TestComplexMixedChains::test_complex_enrichment_dependency_chain graphistry/tests/compute/test_gfql_hypergraph.py::TestGFQLHypergraph::test_hypergraph_typed_builder_with_let graphistry/tests/compute/test_gfql_hypergraph.py::TestGFQLHypergraph::test_hypergraph_with_chaining_in_let graphistry/tests/test_policy_hooks.py::TestOpenTelemetryIntegration::test_nested_query_span_hierarchy_success -q
• uv run env PYTHONPATH=. pytest graphistry/tests/compute/test_gfql_hypergraph.py -q

[lmeyerov]

cudf?

[lmeyerov]

Superseded by #895, #896, and #897.