feat: scaffold mvp shell and content runtime

js/content/registry/continent-registry.js

@@ -0,0 +1,21 @@
+export function createContinentRegistry(continents) {
+  const continentMap = new Map(
+    [...continents]
+      .sort((left, right) => left.sortOrder - right.sortOrder)
+      .map((continent) => [continent.id, continent]),
+  )
+
+  return {
+    getContinentList() {
+      return [...continentMap.values()]
+    },
+    getContinent(continentId) {
+      return continentMap.get(continentId) ?? null
+    },
+    hasContinent(continentId) {
+      return continentMap.has(continentId)
+    },
+  }
+}
+
+export default createContinentRegistry