PhysicalASAPDAG::validate does not check per-operator timing #656

Found in the #541 review.

Problem

PhysicalASAPDAG::validate (and with_execution_phases) checks edge roles and the query-time → ingestion-time edge rule, but not the timing each operator kind requires. For example, it accepts:

• Scan → SummaryAgg → Finalize with every node at ingestion time, which the timing pass rejects as MaintenanceRowsAtRoot;
• a SummaryAgg whose output_state.primitive is Raw.

It doesn't check:

• that SummaryEstimate / EvaluatePopulation run at query time and MaintainPopulation at ingestion time;
• the ingestion-time BinaryOp rules;
• that primitive equals what data_state derives.

Today only the compiler produces these DAGs, from plans the timing pass has already checked, so nothing invalid reaches the runtime. It matters once a DAG is deserialized or re-phased, as in the backend stack. The runtime branches on output_state.timing: an ingestion-time BinaryOp compiles to aligned_binary, which ignores vector_match.

Possible fix

In validate, check each node's timing and primitive against its operator kind, reusing the rules in ir/timing.rs and data_state rather than copying them.