Add sb metadata

design-system-website is reading /metadata.json as HTML

Ref: https://github.com/hashicorp/structure/pull/81 and https://github.com/hashicorp/design-system-website/pull/20

addons/rose/metadata.json

@@ -0,0 +1,5 @@
+{
+  "versions": {
+    "main": "https://boundary-ui-storybook.vercel.app"
+  }
+}

addons/rose/package.json

@@ -9,7 +9,7 @@
   ],
   "scripts": {
     "build:development": "ember build",
-    "build": "ember build --environment=production",
+    "build": "ember build --environment=production && cp metadata.json dist/metadata.json",
     "lint": "npm-run-all --aggregate-output --continue-on-error --parallel 'lint:!(fix)'",
     "lint:fix": "npm-run-all --aggregate-output --continue-on-error --parallel lint:*:fix",
     "lint:hbs": "ember-template-lint .",