Bump to v0.3.1 — fix legacy migration bug

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://json.schemastore.org/package.json",
   "name": "whiteport-design-studio",
-  "version": "0.3.0",
+  "version": "0.3.1",
   "description": "Whiteport Design Studio - Strategic design methodology for AI-powered workflows",
   "keywords": [
     "design",