Step 19 of v4.1 — extend-in-place per brief Preferences. Three new test
blocks asserting forward-compat:
1. Legacy fixtures (plan-run-A.md, plan-run-B.md) — without profile_used
in frontmatter — still parse cleanly after manifest-yaml.mjs added
OPTIONAL_STRING_KEYS.
2. New fixtures (profile-plan-run-{economy,premium}-*.md) — with
profile_used in frontmatter — parse cleanly with correct profile
value extracted.
3. Real v4.1 plan (.claude/projects/2026-05-08-voyage-v4.1-modellprofiler/plan.md)
validates strict, emits no PLAN_VERSION_MISMATCH warning.
Tests: 475 pass + 2 skipped (Docker not installed).
Kjell Tore Guttormsen
93c6b82f62