land-the-plan: task manifest helper uses unavailable mapfile

[ericpassmore]

Incident

• Source repo: OrderPortLLC/core-api
• Task: useful-config
• Skill or stage: land-the-plan / task-manifest-land-update.sh
• Incident type: bug
• Severity: medium

Observation

• What happened: /.codex/scripts/task-manifest-land-update.sh useful-config compacted task artifacts, then failed with line 127: mapfile: command not found.
• Expected: The landing helper should complete manifest metadata update, compaction commit, and push on the supported local shell.
• Can work continue safely: Yes, because compaction completed and the remaining changes are visible in git status; landing can continue with a bounded manual commit of the compacted artifacts.

Evidence

• Repro or minimal steps: Run /Users/passmore/orderport/repos/core-api/.codex/scripts/task-manifest-land-update.sh useful-config in this repo after implementation commit.
• Relevant files/artifacts: /Users/passmore/orderport/repos/core-api/.codex/scripts/task-manifest-land-update.sh, /Users/passmore/orderport/repos/core-api/tasks/useful-config/
• Workaround used (if any): Record issue, inspect partial compaction state, then safely stage/commit/push the compacted manifest/task artifact changes manually.

Additional observed wrapper issue: ./.codex/scripts/gh-wrap.sh issue create ... failed locally with ${owner,,}: bad substitution, so this issue was filed through the GitHub connector fallback.