feat(content): promote Duncarrow; build client/server artifacts

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

content/world/topics/crell-runs-slave-trade.json

@@ -0,0 +1,9 @@
+{
+  "id": "secret.crell-runs-slave-trade",
+  "related": [
+    "person.mayor-oswin-crell",
+    "place.the-white-antlers",
+    "faction.elves"
+  ],
+  "type": "secret"
+}