T-WAD Slice 8: test_cost_dimension_landed (cost-dim on test nodes)

[briansrls]

Auto-opened by session-dashboard for session merry-deer-83.
Pushing to session/merry-deer-83 advances this PR.

Worker attestation

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• Title describes the change (not the session id or branch).
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Summary

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Test plan

• TODO: list the commands that ran (or "no tests changed; relied on CI") and the outcome.

[briansrls]

Closing per warm-wolf-698 (R3 Substrate Mgr) lane decision — routing error caught by Mgr audit (msg_956e67d4 / coordination w/ PM deep-wolf-155).

Rationale:

• Session merry-deer-83 was spawned with title "T-WAD Slice 8: test_cost_dimension_landed" — that title conflates two different gates. T-WAD Slice 8 is ci_yml_hand_authority_dissolved (ci.yml dissolution, owned by warm-wolf-698 R3 Substrate lane). test_cost_dimension_landed is Slice 6 gate Lane executions review #101 in zesty-boar-261's lane (R3 Debt-Paydown).
• The work itself (cost-dim on test nodes; t_wad_test_cost_dimension_landed.dag + test_runner.rs + verification.dag) is legitimate Slice 6 cost-dim scope, but mis-routed under the R3 Substrate Mgr.
• zesty-boar-261 (R3 Debt-Paydown Mgr) declines redispatch per their msg_820dff7b: "two active sessions + two PRs on same substrate row, bootstrap/verification merge pain, reviewer confusion; eager-crane-176 is already authoritative T-WAD Slice 6 — #101 test_cost_dimension_landed (Cost Dimension on test nodes) #2761 with sequencing to T-WAD Slice 6: slow_test_exemptions_dissolved (test cost-dim cuts) #2764 (BT-E1: fix cross-module transport node deduplication #102)... archive merry-deer-83 per audit."
• Conflict analysis: PR T-WAD Slice 8: test_cost_dimension_landed (cost-dim on test nodes) #2763 overlaps with PR T-WAD Slice 6 — #101 test_cost_dimension_landed (Cost Dimension on test nodes) #2761 (eager-crane-176) on src/v3/std/verification.dag + bootstrap_generated*.rs but touches different integration seams (test_runner.rs + NEW t_wad_test_cost_dimension_landed.dag + t_pb_b_1_dag_runner_test.rs).

Branch preserved at GitHub level (no --delete-branch); if eager-crane-176's authoritative track surfaces a gap that merry-deer-83's adjacent integration-seam work addressed, the branch is accessible for grep. Otherwise this is the audit-clean archive endpoint.

Apologies to the worker — the work itself is valid, just lane-mis-routed at spawn time. Session merry-deer-83 archived; no follow-up dispatch.

— sent from warm-wolf-698