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/npcs/mayor-oswin-crell.json

@@ -0,0 +1,23 @@
+{
+  "id": "npc.mayor-oswin-crell",
+  "knows": [
+    {
+      "fact_id": "rumor.elves-avoid-the-shrine",
+      "gate": "cold"
+    },
+    {
+      "fact_id": "secret.crell-runs-slave-trade",
+      "gate": "never"
+    },
+    {
+      "fact_id": "fact.crells-guard-acts-alone",
+      "gate": "never"
+    }
+  ],
+  "related": [
+    "person.mayor-oswin-crell",
+    "secret.crell-runs-slave-trade"
+  ],
+  "start_disposition": "neutral",
+  "type": "person"
+}