flameshot full dies docked: its portal path hits niri's
screenshot_all_outputs ensure!(outputs.len()==1) (upstream niri#4313,
niri 26.04), so every Print press on the home desk produces error
bubbles. niri's built-in screenshot UI selects only one output, so add
scripts/screenshot-desk.sh: per-monitor focus + screenshot-screen with
explicit --path, focus restored, one PNG per monitor in
~/Pictures/Screenshots. Bind Mod+Shift+S (Frank's call); noctalia
settings moves to Mod+Shift+O. Restore screenshot-path (was null, now
root-level as config.screenshot_path requires) for UI saves. Live-
verified docked: valid 1920x1080 PNGs for eDP-1 + DP-2, focus restored;
bats 27/27 incl. niri validate on both desk profiles.
Host-specific divergence for blankpad deployed last with override semantics:
display layout (its own outputs, not Dankware's DP/eDP rig), autostart and
keybinds targeting the bare 'noctalia' CLI instead of qs -c noctalia-shell,
misc without renderD129, rules without the Noctalia floating-window rule, and
blank's own .zshrc. All other packages deploy canonical from base.