chore: add changeset for init scaffold ownership fix

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: os-zhuang

.changeset/init-scaffold-drop-ownership.md

@@ -0,0 +1,7 @@
+---
+"@objectstack/cli": patch
+---
+
+fix(cli): drop stale `ownership` key from the `os init` scaffold object template
+
+The `app` and `plugin` scaffold templates emitted `ownership: 'own'` on the starter object. `ownership` is no longer a valid `ObjectSchema` field (it's not in `ObjectSchemaBase`, and `ObjectSchema.create()` rejects unknown top-level keys per ADR-0032 / #1535), so a user migrating the scaffolded object into `ObjectSchema.create({...})` would hit a validation error. Removed the key from both templates; the rest of the scaffold output is unchanged.