Fix boot-critical, session, and UX bugs found in round-3 UX audit

Snapshots panel was non-functional (wrong snapper flag); breadgreet picked
the wrong session .desktop and skipped bos-session's PATH fixup; Calamares
aborted offline installs over an unnecessary packages module; snapshot
rollback silently no-op'd on BOS's pinned-subvolume layout (now points at
grub-btrfs instead); breadcrumbs was configurable but had no daemon to run
it. Also: SUPER+I double-bind, breadpaper/packages panels blocking the GTK
main thread, dead polkit rule, and a sweep of smaller drift (default
sidebar view, stale wording, missing .desktop launchers, wallpaper daemon
not recording its own default).

src/ui/views/mod.rs

@@ -3,6 +3,7 @@ pub mod breadbar;
 pub mod breadbox;
 pub mod breadcrumbs;
 pub mod breadpad;
+pub mod breadpaper;
 pub mod breadsearch;
 pub mod hyprland;
 pub mod packages;