The Share Extension's session had no delegate, so a fast upload finished
unseen and the invalidated session was discarded before the app could hear of
it - no summary notification. Results are now handled by a shared delegate in
whichever process is alive, started/finished notifications replace each
other in place, and the app refreshes the folder the extension uploaded to.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
SwiftUI folder picker in the extension (WebDAV PROPFIND), account shared via
a Keychain group, upload on a background session that outlives the extension
and is finished by the app. The inbox + notification hand-off remains as the
fallback (no account / 'choose later'). Shared code moves to ios/Shared.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
