docs(content): roadmap — Duncarrow purged, ladder in mechanics.md, specimen added

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HuHRPE7VfppUJEaoGBEUqZ

content/lore/canon-roadmap.md

@@ -18,11 +18,12 @@ order the Margreave is being written. Source of truth is `content/lore/*.md`;
   warlock's former `[CANON-TBD]` name) pacts one of the Seven. Applying `Bloodsworn` to calling
   data and a Bloodsworn's patron choice are M4; any Luck effect is an M5/
   Improviser reconcile.
-- **duncarrow.md** — the bounded-dialogue / disposition-gate specimen (Duncarrow,
-  the Crell chain, Mera Fenn, etc.). **Scaffolding, not story:** it seeded the
-  schema + skill and hosts the required-once `rule.disposition-ladder`. Slated for
-  removal in a follow-up that reparents the ladder into `cosmology.md` and stands
-  up a cosmology-native specimen town.
+- **mechanics.md** — hosts `rule.disposition-ladder` (the required-once gate
+  vocabulary), reparented out of the retired Duncarrow scaffolding.
+- **specimen.md** — a synthetic `status: candidate` disposition-gate specimen
+  (validated by `--check`, emitted nowhere); the world-building skill's structure
+  example. Not game canon. The Duncarrow scaffolding (Crell chain, Mera Fenn) is
+  deleted.
 
 ## Pending (not yet authored)