feat(export): include summary lifecycle alternatives and rejections

[zzylol]

Summary

Connects the selected summary-maintenance plan to DAG export.

export_summary_maintenance_plan emits:

• the materialized post-ASAP graph;
• unique summary deployments;
• selected lifecycle guarantees;
• all considered alternatives;
• costs and assumptions;
• stable typed rejection reasons;
• horizon, demand rates, expected reads, and raw-recompute comparison.

The mapping-layer adapter preserves the dependency boundary: asap-types::dag_export remains unaware of optimizer-specific lifecycle vocabulary.

Export assertions locate alternatives by lifecycle kind rather than array position.

Verification

• cargo test -p asap-integration-tests --test workload_lifecycle_e2e
• cargo clippy -p asap-aware-mapping -p asap-integration-tests --all-targets --all-features --locked -- -D warnings
• cargo check --workspace --locked

Stack

Base: #320.