L2: compile() builds Arc<Value> once and threads &Arc<Value> down the
compile walk; every real ReadPlan carries the document at construction
— the Value::Null-placeholder-then-map-overwrite dance is gone. The one
remaining Null in wrap_leaf is documented as correct-by-construction
(anonymous synthetic wrapper, never escapes).
L3: materialize_plan_field drops its plan parameter (taken solely to
discard) and the field-disc union arm's disc_field/let _ pair is
deleted — the order-walk + by-name capture is the materializer's
correct design, as the finding's parity note described.
508 tests green, clippy -D warnings clean, wasm32 build green,
cargo doc zero warnings.
glm-5.3-flash
8739d29550