feat(voyage): bump trekbrief-template to brief_version 2.1 + add phase_signals fixtures

plugins/voyage/templates/trekbrief-template.md

@@ -1,6 +1,6 @@
 ---
 type: trekbrief
-brief_version: 2.0
+brief_version: 2.1
 created: {YYYY-MM-DD}
 task: "{one-line task description}"
 slug: {slug}
@@ -10,6 +10,20 @@ research_status: pending         # pending | in_progress | complete | skipped
 auto_research: false             # true if user opted into Claude-managed research
 interview_turns: {N}
 source: {interview | manual}
+# v5.1 — per-phase effort + model signal (Phase 3.5).
+# `effort` ∈ {low, standard, high}. Omit `model:` for `standard` so composition
+# falls through to profile resolver. Force-stop alternative is the commented
+# `phase_signals_partial: true` below (mutually exclusive with `phase_signals`).
+phase_signals:
+  - phase: research
+    effort: standard
+  - phase: plan
+    effort: standard
+  - phase: execute
+    effort: standard
+  - phase: review
+    effort: standard
+# phase_signals_partial: true   # uncomment to record force-stop instead of phase_signals
 ---
 
 # Task: {title}