📜 v2.9.0 - In-app changelog

• New: native in-app Changelog screen, opened from Settings and the "What's New" sheet
• New: Contributors screen in About
• New: text in the markdown preview is now selectable
• Fix: developer options stay visible until the app restarts
• Updated translations: Spanish, Chinese (Simplified)

Thanks to victoriamontero443-wq, PaikLC and heretic43!
