fix(brief): require PR with green CI as no-mistakes terminal condition

[jgrizon]

Summary

Fix the no-mistakes definition of done in bin/fm-brief.sh so crewmate worker briefs specify a PR with green CI as the only terminal condition, and explicitly state that a local commit, green local test suite, and completed pipeline step are all NOT done.

Generated no-mistakes section

Before

# Definition of done
Delivery contract: mode=no-mistakes
The task is complete only when committed on your branch.
When you believe it is complete, append `done: {summary}` to the status file and stop.
Firstmate will then instruct you to run /no-mistakes to validate and ship a PR.

You drive no-mistakes by responding to its gates, not by implementing fixes.
Follow the guidance no-mistakes itself provides for the mechanics: it loads when you invoke /no-mistakes, and `no-mistakes axi run --help` plus the `help` lines in each `axi` response are authoritative and version-matched to the installed binary.
When starting no-mistakes, make `--intent` preserve all relevant content from this brief's `# Task` section plus every later accepted Firstmate requirement, clarification, constraint, exclusion, and supersession, carrying only each requirement's current accepted form; retain direct requirements instead of substituting a diff summary, and exclude generic operational, status, delivery, and other scaffold boilerplate unless it is task-specific.
Do not hand-edit, commit, or fix findings yourself while a run is active - the pipeline applies every fix.

Two firstmate-specific rules layer on top of that guidance:
- ask-user findings are never yours to answer: escalate to firstmate (rule 6) and stop.
  Firstmate applies the authority contract in its `AGENTS.md` and obtains any required captain decision.
  When the decision comes back, feed it to the gate with `no-mistakes axi respond` and let the pipeline apply it - do not route the question to "the user" or implement the fix yourself.
- Avoid `--yes`: it would silently bypass firstmate's authority check and any required captain escalation.

After /no-mistakes reports CI green (the CI-ready return point - do not wait for it to keep monitoring in the background until merge), append `done: PR {url} checks green` and stop. You are finished.

After

# Definition of done
Delivery contract: mode=no-mistakes
This task ships via **/no-mistakes**.
The task is done only when a PR exists and its CI is green (`done: PR {url} checks green`), never when a local test run passed.
A local commit, a green local suite, and a completed pipeline step are all NOT done.
When your changes are ready, run /no-mistakes to validate and ship a PR.

You drive no-mistakes by responding to its gates, not by implementing fixes.
Follow the guidance no-mistakes itself provides for the mechanics: it loads when you invoke /no-mistakes, and `no-mistakes axi run --help` plus the `help` lines in each `axi` response are authoritative and version-matched to the installed binary.
When starting no-mistakes, make `--intent` preserve all relevant content from this brief's `# Task` section plus every later accepted Firstmate requirement, clarification, constraint, exclusion, and supersession, carrying only each requirement's current accepted form; retain direct requirements instead of substituting a diff summary, and exclude generic operational, status, delivery, and other scaffold boilerplate unless it is task-specific.
Do not hand-edit, commit, or fix findings yourself while a run is active - the pipeline applies every fix.

Two firstmate-specific rules layer on top of that guidance:
- ask-user findings are never yours to answer: escalate to firstmate (rule 6) and stop.
  Firstmate applies the authority contract in its `AGENTS.md` and obtains any required captain decision.
  When the decision comes back, feed it to the gate with `no-mistakes axi respond` and let the pipeline apply it - do not route the question to "the user" or implement the fix yourself.
- Avoid `--yes`: it would silently bypass firstmate's authority check and any required captain escalation.

After /no-mistakes reports CI green (the CI-ready return point - do not wait for it to keep monitoring in the background until merge), append `done: PR {url} checks green` and stop. You are finished.

Verification

• bin/fm-lint.sh passes cleanly (ShellCheck 0.11.0, actionlint 1.7.12).
• tests/fm-brief.test.sh passes all 20 behavior checks including updated and new assertions for no-mistakes terminal conditions and false-finish exclusions.
• bash tests/fm-ask-user-authority.test.sh passes.

ok - fm-brief.sh: bash -n succeeds
ok - fm-brief.sh: no heredoc is nested inside a command substitution (Bash 3.2 parse-safe)
ok - fm-brief.sh: --help renders the complete header
ok - fm-brief.sh: no-mistakes/direct-PR/local-only briefs generate cleanly
ok - fm-brief.sh: ship --mode is required and closed-set validated
ok - fm-brief.sh: the explicit ship mode wins over the registered posture
ok - fm-brief.sh: --yolo and scout/secondmate --mode are refused, never silently dropped
ok - fm-brief.sh: faster paths use configured authority without stacked review
ok - fm-brief.sh: no-mistakes DOD keeps its apostrophe prose, now parse-safe
ok - fm-brief.sh: ship project-memory wording carries the AGENTS.md authoring bar
ok - fm-brief.sh: --herdr-lab emits the complete hard safety contract
ok - fm-brief.sh: --herdr-lab uses its quoted Firstmate-owned helper path
ok - fm-brief.sh: ship and scout scaffolds make omitted Herdr intent fail-visible
ok - fm-brief.sh: Herdr lab contract covers scouts and rejects secondmate misuse
ok - fm-brief.sh: --no-projects scaffolds a project-less charter and guards misuse
ok - fm-brief.sh: marked requests avoid generic acknowledgements and preserve material reporting
ok - fm-brief.sh: relative directory inputs ignore CDPATH, render stable absolute charter paths, or fail loudly
ok - fm-brief.sh: custom pause verb renders in every scaffold
ok - fm-brief.sh: investigation and visual-review completions load the shared decision policy
ok - fm-brief: scout and secondmate code paths still scaffold well-formed briefs