🔖(major) release 3.0.0

Added:
- 📄(legal) Require contributors to sign a DCO

Changed:
- ♻️(frontend) Integrate UI kit
- 🏗️(y-provider) manage auth in y-provider app

Fixed:
- 🐛(backend) compute ancestor_links in get_abilities
  if needed
- 🔒️(back) restrict access to document accesses

src/frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "impress",
-  "version": "2.6.0",
+  "version": "3.0.0",
   "private": true,
   "workspaces": {
     "packages": [