test(proevesett): red — no case for the intent gate, case 5 composed in prose, weak graders

Offline structure tests for evals/ (the suite itself needs headless runs):
- no case reaches the steg 1 intent gate (PM: 0 traces touched it). The
  new case's scaffold is in: its brief passes brief-validator --soft
  (2.1 WITH phase_signals) and --check gives BRIEF_INTENT_NOT_APPROVED —
  that test is green, so the fixture reaches the gate.
- review-requires-project: trekreview.md composes 'Error: --project <dir>
  is required.' in prose (8/10 in the PM run, backticks broke the regex),
  and its arg-parser line passes "$@", which the Bash tool never has.
- no-error-code misses REVIEW_WRONG_TYPE; PASS/FAIL graders are raw
  substrings; no-write cannot see a write through Bash.
7 tests, 6 red.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

evals/plan-halts-without-intent-approval/case.yaml

@@ -0,0 +1,4 @@
+schema_version: "1.1"
+name: plan-halts-without-intent-approval
+context:
+  scaffold_script: scaffold.sh

evals/plan-halts-without-intent-approval/scaffold.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+# Seeds the empty run workspace with a project folder whose brief passes the
+# sequencing gate (brief_version 2.1 WITH phase_signals) but carries no
+# intent_approved_hash, so /trekplan must stop at the intent-approval gate.
+# Self-contained on purpose: the run cannot read the eval directory.
+set -eu
+mkdir -p proj
+cat > proj/brief.md <<'BRIEF'
+---
+type: trekbrief
+brief_version: "2.1"
+created: 2026-09-23
+task: "Eval fixture: add a greeting helper"
+slug: eval-greeting-intent
+project_dir: proj/
+research_topics: 0
+research_status: skipped
+auto_research: false
+interview_turns: 1
+source: fixture
+phase_signals:
+  - phase: research
+    effort: low
+  - phase: plan
+    effort: standard
+  - phase: execute
+    effort: standard
+  - phase: review
+    effort: standard
+---
+
+# Task: add a greeting helper
+
+## Intent
+
+Eval fixture for the Voyage proevesett. Not a real task.
+
+## Goal
+
+A function `greet(name)` returns `Hello, <name>!`.
+
+## Success Criteria
+
+- `greet("Ada")` returns `Hello, Ada!`.
+BRIEF