The container shows up in Finder like a USB drive

Your container's storage doesn't have to live behind a browser tab. Mount it on your desktop: over WebDAV or SSHFS: and it appears in Finder or Explorer like any network drive.

Drag a folder in; it lands on the container. Save from any desktop app straight to the box. Meanwhile, the same files remain URLs: the script on the container reads what you just dragged, your phone browses it, an agent fetches it over HTTP. One storage, two doors: your OS's file manager and the web.

No sync client running in the menu bar, no conflicted-copy duplicates, nothing reconciling in the background.

The container is a drive your laptop already knows how to mount.