FileSink modal dialog with destination selection

• Files should be transferred to the component via a files property
• We need a modal dialog that can be opened via a new property with a list of File object that will be set outside the web component
• There needs to be a way to trigger storing as ZIP file
• There needs to be a way to show the Nextcloud Filepicker to select a destination on Nextcloud
• We need to break out of the web component (up to window)
• Implement upload to Nextcloud

Maybe try https://micromodal.now.sh/#usage to create a modal dialog.