Delete dead stage0 std_lens_verdict by its authorities (layout registration, retention frontier, file, regenerated layout artifacts) and settle the orphan src/v1/stage0_core with a search receipt

[briansrls]

Summary

Delete the dead stage0 std_lens_verdict source through its two authorities: remove its crate-layout registration and seed-retention-frontier row, delete the Rust file, and regenerate both checked-in layout artifacts. Delete the unowned src/v1/stage0_core crate and dissolve its lifecycle residue contradiction.

The durable search receipt is gunbc.v1_consumer_census stage0_core_deletion_search_receipt. Its search covered workspace members, every tracked Cargo manifest/path dependency, workflow/emission/tooling references, the authored partition authority v2.workflow.rust_crate_partition, and gunbc.stage0_crate_partition_generated; no builder or owner named the orphan.

Search receipt

rg -n "stage0_core|v1-stage0-core" over tracked files found only the orphan itself and its pre-existing lifecycle/census contradiction. After deletion, remaining stage0_core hits are the durable receipt and its retirement row.

Remaining std_lens_verdict hits are intentional history/fixture controls in the partition authority and its existing discriminating witness; neither the live layout authority nor either regenerated layout artifact retains the filename.

Test plan

• cargo fmt --all --check - passed in both commit/push hooks.
• ctrl-build --remote -- cargo build --release --workspace - passed at exact commit d5294bab3a (BuildBuddy).
• GitHub rust-unit-tests - passed.
• Required build/floor lanes - running on the regenerated-artifact commit.

[gunbai-bot]

Addressed both findings from review 57553 in 7c813da:

• regenerated src/v1/stage0/src/gunbc_stage0_crate_layout_generated.rs so its projection no longer contains std_lens_verdict.rs;
• regenerated .gitattributes so the deleted path no longer carries a stale !merge row.

A focused search across all four layout projections plus .gitattributes now returns no live std_lens_verdict entry. — sent from loyal-deer-851