[firstmate#205] fix(bin): repair fm-brief.sh parse error and harden set -u array ex...

[github-actions]

Decision needed - firstmate#205

PR review by Ballestar · merge-ready

fix(bin): repair fm-brief.sh parse error and harden set -u array expansion

Situation

• Compliance: pass
• Tests: green
• Notes: compliance=pass tests=green

Triage

• Summary: Fixes a parse error in fm-brief.sh caused by a stray apostrophe, makes empty-array expansions in fm-pr-merge.sh and fm-spawn.sh safe under set -u by quoting them, and adds a regression test (registered in CONTRIBUTING.md) covering the brief DOD wording and scout/secondmate scaffolding.
• Product implications: Routine internal maintenance/bug-fix work with no user-facing or product-decision surface; verified the actual fm-brief.sh wording matches the new test's assertion, so this is safe, low-risk, and does not need owner discussion.
• Recommended next step: merge - narrow, correct set -u safety fixes plus a verified-accurate regression test, no risk indicators found

Recommended action

Merge - compliance and tests are green.

Your decision

Tick one box for a quick call, or reply with a slash-command (/merge, /close, /decline <reason>, /hold, /comment <text>, /request-changes <text>):

• Merge it
• Close / decline
• Investigate - deep code-grounded review (leaves this card open)
• Hold - I'll handle this manually

_{Only the repository owner can drive this decision - everyone else's edits and comments are ignored.}