[richardgetz]

Why

Forks currently receive a daily stale-PR schedule event whose job is skipped, and matching upstream Rust, V8, or zsh release tags can start expensive release graphs in the fork. The fork's release path is the separate stable workflow.

Change

• Remove the daily schedule from stale-contributor-PR cleanup while retaining its manual dispatch and canonical-only job guard.
• Guard the root jobs of the upstream Rust, V8, and zsh tag-release workflows to openai/codex, so fork tag pushes stop before runner allocation. Their tag triggers remain intact upstream.
• Record the fork-only policy and refresh checks in the fork delta inventory.
• Keep the fork's automatic stable release, required PR checks, and reusable/manual CI workflows unchanged.

Validation

• All four changed workflow files parse as YAML.
• actionlint 1.7.12 reports no new diagnostics. The two unfiltered rust-release.yml diagnostics (matrix.runs_on inference and concurrency.queue schema) also reproduce on base stable and were excluded from the changed-file check.
• Static trigger/graph checks confirm manual stale-PR dispatch remains, the daily schedule is gone, the canonical guard is false for richardgetz/codex, and every job in each tag-release workflow descends from its guarded root.
• git diff --check passes; fork-release.yml, blocking CI, and reusable CI workflows are unchanged.
• GitHub checks pass for format/shear, argument lint on Linux/macOS/Windows, blob-size policy, codespell, changed-area detection, and release metadata. Bazel and SDK jobs were correctly skipped for this docs/workflow-only diff.
• cargo-deny and the required CI required summary fail on 9 dependency vulnerability advisories and unmaintained unsafe-libyaml (failed job). This diff changes no dependency inputs, so remediation is outside this PR.
• Two independent reviews found no remaining issues. No Rust tests were run because the diff is workflow and documentation only.

Fork compatibility checklist

• Updated codex-rs/core/templates/fork/delta_inventory.md.
• Added the corresponding Merge Checklist item.