ridafkih/keeper.sh ? reverse-engineered prompt

Build me a self hosted calendar sync app that lets me connect Google Calendar, Outlook, Office 365, iCloud, Fastmail, CalDAV, and public ICS links, then keep one or more destination calendars in sync automatically.

I want a simple web app where I can add my calendars, choose which ones are sources and which ones are targets, and see that the events are being pulled, copied, updated, and removed correctly when something changes on the source. It should avoid stale events, keep track of what it created, and make it easy to clean up old synced items.

Also include an MCP server so my AI tools can read and manage my calendars from one place. Make the app feel polished and easy to use, with a clear setup flow, login, and a dashboard for sync status. If you need to look up current docs online for any of the calendar or auth integrations, do that.