GFQL/test triage grab-bag

[lmeyerov]

Summary

• improve ASTCall schema validation and update topology/schema tests
• adjust boundary call handling to avoid chain() deprecation in tests
• register pytest tier2 mark and unskip parallel ASTRef chain test
• drop resolved cudf/neo4j xfails; migrate compute tests to gfql
• fix pandas bool fillna warning and relax bool/object filter mismatch
• update Development changelog (schema/filters)

Testing

• uv run env PYTHONPATH=. pytest graphistry/tests/compute/test_chain_let.py graphistry/tests/compute/test_astcall_topology.py graphistry/tests/compute/test_call_schema_validation.py -q