fix: outside-voice fallback is labeled honestly — same model family, not cross-model (#2735)

When Codex is unavailable, the plan-review outside voice falls back to a
Claude subagent and the copy sold it as 'cross-model coverage' with 'genuine
independence'. Fresh context is real; cross-model validation is not — a user
weighing 'both reviewers agree' deserves to know both reviewers share a model
family. Six canonical strings fixed at the resolver source (constants.ts
not_installed/not_authed, review.ts outside-voice bullet + three dispatch
paragraphs); ~10 generated docs and the ship goldens regenerated. Printing
the resolved fallback model at dispatch time is descoped as a functional
change (follow-up in the wave dispositions).

Fixes #2735

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

test/helpers/carve-guards.ts

@@ -512,7 +512,7 @@ export const CARVE_GUARDS: Record<string, CarveGuard> = {
     },
     behavioral: 'external',
     externalTest: 'test/skill-e2e-autoplan-chain.test.ts', // phase-complete markers live ONLY in sections — its assertions ARE section-read proof
-    maxSkeletonBytes: 64_500, // + v1.78 AUQ spawned-trigger objectivity (explicit declaration + interactive fence); measured 64_106
+    maxSkeletonBytes: 65_100, // + v1.78 AUQ objectivity + #2745 broken-install preflight arm + outside-voice honest labeling; measured 64_668
     minUnionBytes: 85_000, // measured union 86,926
     mustContain: ['6 Decision Principles', 'TASTE DECISION', 'USER CHALLENGE', 'consensus', 'Restore Point'],
   },