WalkPlan schedule lens covers success-stage structure

[briansrls]

Closes the gap where the schedule lens inspected only the ordinary RealizationPlan while the executor consumed a WalkPlan with a second on-success population.

This change narrows the old function to schedule_lens_verdict_for_ci_floor_ordinary and adds the complete WalkPlan wrapper. The wrapper joins authored batches to the ordinary planner projection, consumes the modeled std.realization_schedule on-success disposition, and compares ordered stage barriers with unordered sibling multisets using full runnable identity. Duplicate identity refuses across the staged population.

The production CI plan now derives its deliberately empty stage roster from gunbc_ci_on_success_stages. A dedicated blocking floor witness replaces the stale AuditOnly/NoConsumerWitness contract metadata. Synthetic nonempty controls execute the complete verdict table, including sibling reorder green and dropped, duplicated, flattened, split, reordered, or inadmissible stages red. Finalization remains deliberately separate under its existing witnesses and strict runtime parser.

Verification:

• direct production witness: true
• synthetic mutation matrix: true
• scoped target-dag compile: 0 blocking errors
• regen_stage0 generated and committed the std projection
• cargo fmt --all --check via hooks

Sequencing: remains draft until prerequisite #7518 merges, then main will be integrated and the shared std carrier regenerated before ready-for-review.