Summary

• Add per-command-hook run_in_subagents / runInSubagents config with default true.
• Skip opted-out hooks in non-root/subagent sessions across hook event types.
• Expose runInSubagents in hooks/list metadata and update docs/schemas.

Test Plan

• just fmt
• cargo test -p codex-config run_in_subagents
• cargo test -p codex-hooks
• cargo test -p codex-app-server hooks_list
• cargo test -p codex-app-server-protocol
• just fix -p codex-config
• just fix -p codex-hooks
• just fix -p codex-app-server
• just fix -p codex-app-server-protocol

Notes

• Full cargo test was not run because repository instructions require asking before running the complete suite; focused affected suites passed.
• The local /home/k3/.codex/hooks.json Superpowers hook opt-out was applied locally and is not part of this PR.