Bake bread ecosystem into the ISO + full live desktop; fix installer timeout

- packages.x86_64: add bread, breadbar, breadbox, breadcrumbs, breadpad,
  bos-settings so they ship in the squashfs and reach the target via unpackfs
  (no network needed; install works fully offline)
- shellprocess.conf: set timeout 1800 — Calamares' 10s default was killing
  post-install.sh partway (the real cause of the empty /boot + ESP); the "-"
  prefix had been masking the kill as success
- bos-live-setup: live user now boots the real BOS desktop from /etc/skel
  (breadd + breadbar + breadbox) with the installer layered on top
  (auto-launch + Super+I), instead of an installer-only kiosk
- post-install.sh: drop the now-redundant networked `bakery install`

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

iso/airootfs/etc/calamares/modules/shellprocess.conf

@@ -1,3 +1,9 @@
 ---
+# Calamares defaults shellprocess to a 10-second timeout. post-install.sh runs
+# mkinitcpio, grub-install, grub-mkconfig, snapper setup and a networked bakery
+# install — minutes of work — so without a generous timeout it gets killed
+# partway (leaving /boot and the ESP half-populated → unbootable system). The
+# leading "-" keeps a non-zero exit non-fatal to the install.
+timeout: 1800
 script:
   - "-/usr/bin/bash /etc/calamares/post-install.sh"

iso/airootfs/etc/calamares/post-install.sh

@@ -81,14 +81,9 @@ fi
 systemctl enable NetworkManager bluetooth snapper-cleanup.timer grub-btrfs.path \
     || echo "WARN: enabling some services failed"
 
-# ---------------------------------------------------------------------------
-# Bread ecosystem via bakery (needs network — non-fatal so an offline install
-# still completes; the user can run it after first boot).
-# ---------------------------------------------------------------------------
-if [[ -n "$MAIN_USER" ]] && command -v bakery &>/dev/null; then
-    sudo -u "$MAIN_USER" bakery install bread breadbar breadbox breadcrumbs breadpad bos-settings \
-        || echo "WARN: bakery install failed (no network during install?); run it after first boot"
-fi
+# The bread ecosystem (bread, breadbar, breadbox, breadcrumbs, breadpad,
+# bos-settings) is baked into the squashfs and already copied onto the target by
+# unpackfs — no install step needed here, and the install works fully offline.
 
 # ---------------------------------------------------------------------------
 # Deploy dotfiles into the user's home (don't clobber existing files).