Changelog for the upcomming release (preview)

Changes

• Migration to Vue 3 and Pinia

What's Changed

🚀 Enhancements

• cast activity rich object paramaters to string by @dartcafe in nextcloud#3908

🐛 Fixed bugs

• fix preferences === null by @dartcafe in nextcloud#3907

Full Changelog: v8.0.0-alpha8...v8.0.0-alpha13