Changing pages in the notifications or devices list gave no cue that
the next page was loading. Render an indeterminate progress bar at the
shell level, pinned flush against the bottom of the page body (above
the nav bar on phones, the screen bottom on wide layouts), driven by a
shared paginationLoading notifier the lists set while fetching. The
pagination bar keeps disabling its buttons during the fetch.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Extract ScannerStatusCard<T> and PaginationBar so the ARP/mDNS cards and
the two paginated lists share one implementation each. Also fold the
four UISnackbars methods over a severity enum and fix Notification.toJson
serializing a method tear-off instead of the enum name.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
