fix(substrait): detect unsupported fixed-size-list filters

[lance-gatefixer]

Root cause

FilteredReadExec pruned FixedSizeList fields before DataFusion type-checked its filter expressions. A valid predicate referencing a pruned vector field therefore surfaced as FieldNotFound instead of an unsupported Substrait transport.

Fix

Add a reusable expression preflight against the original schema and apply it to options and precomputed-plan filters before pruning. FixedSizeList references now return a typed NotSupported error so distributed callers can retain the predicate on another execution path; filters referencing supported fields around an unreferenced vector continue to round-trip.

Validation

• cargo test -p lance-datafusion --features substrait --lib substrait::tests
• cargo test -p lance --features substrait --lib io::exec::filtered_read_proto::tests
• cargo test -p lance-datafusion --features substrait --doc
• cargo fmt --all -- --check
• cargo clippy --all --tests --benches -- -D warnings

Fixes #9056

[lance-gatekeeper]

✅ Gate recommendation: approve.

The change establishes the capability boundary before schema pruning, so filters that reference unsupported fixed-size-list fields return NotSupported while supported predicates on vector-bearing datasets continue to round-trip. Option and precomputed-plan filters are both covered.