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/canon/the-white-antlers.json

@@ -0,0 +1,9 @@
+{
+  "body": "An old elven shrine a half-hour's walk north of Duncarrow, in the birch stand off the pass road. Weathered antler-carvings, a dry basin, nothing worth stealing. Elves on the road have historically stopped here. Locals know it as a curiosity and a good spot to water horses.",
+  "id": "place.the-white-antlers",
+  "related": [
+    "town.duncarrow",
+    "faction.elves"
+  ],
+  "type": "place"
+}