feat: link dialog finds bullets of all notes; richer sample data with help notes, deep nesting and linked to-dos

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/package.json

@@ -1,7 +1,7 @@
 {
   "name": "mindsift-frontend",
   "private": true,
-  "version": "0.46.0",
+  "version": "0.47.0",
   "license": "Unlicense",
   "type": "module",
   "scripts": {