CloudKit Capacitor for cloud sync

Hello,
I developed my first iOS and macOS application (Electron) with Ionic 6 and Capacitor (http://cupfeed.app for the curious).

However I have a feature I would like to implement now: Cloud synchronization. And ideally via Apple Cloudkit.

I can’t find a Capacitor plugin allowing me to implement this. There is a Key/value system but it is not adapted to my use (only 1 MB of storage)
I tried via the JS version of CloudKit but without success. At least it worked more or less via the browser but the login does not work in Electron or in the iOS app. (and I’m not sure anyway that the user would stay logged in with this trick).

How do you implement this to access the iCloud user’s private database?

Thanks in advance

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