fix(stats): no command promises a stats key its record does not write

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

docs/profiles.md

@@ -118,16 +118,9 @@ Voyage resolves the profile in this priority order:
 3. **`VOYAGE_PROFILE` environment variable** — useful for headless CI
 4. **Default `premium`** — final fallback
 
-The resolved value is recorded in two places:
+The plan-file fields for the resolved value:
 
 - Plan-file frontmatter `profile: <name>` and `phase_models: [...]`
-- Stats stream `${CLAUDE_PLUGIN_DATA}/trek*-stats.jsonl` —
-  `profile`, `profile_source`, `phase_models`, `model_used`,
-  `phase_models_resolved` fields
-
-`profile_source` distinguishes how the profile was resolved (`flag` /
-`plan_frontmatter` / `env` / `default`), so dashboards can surface
-unexpected env-var inheritance in CI.
 
 ## Custom profiles
 
@@ -206,9 +199,8 @@ execute + review) on a moderate-complexity task. Numbers scale roughly
 linearly with the size of the resulting plan (10 steps ≈ baseline; 30
 steps ≈ 3× the execute column).
 
-Per-profile actuals are emitted to JSONL stats — pipe them through the
-OTel export (`docs/observability.md`) to get real cost-attribution
-graphs in Grafana. Replace the table above with your own measured
+The stats records carry no profile field, so they cannot split cost by
+profile. Replace the table above with your own measured
 numbers after ≥ 3 runs of each profile.
 
 ## Deferred to v4.2