The CLI filled only the keys a project lacked from its system preset.
The GUI builds a project preset differently: the project's values go
over the default preset, without the print-host keys, and every key
the project does not list in different_settings_to_system is refreshed
to its base system preset's current value. After a profile update the
two sliced the same project differently.
That step now lives in Preset::load_external_config, which takes plain
configs and gets the base preset from a callback, so the collection
lookup stays in PresetCollection. PresetBundle::project_different_keys
builds the kept-key set from a project's escaped entry, adding the
preset bookkeeping keys, and is used by both the GUI and the CLI.
PresetCollection::load_external_preset calls the shared step with no
change in behaviour.
The CLI now builds the project's printer and process configs with the
same step, passing the system preset from resolve_system_preset. That
drops the hand-kept skip list for print-host and variant-layout keys
and the legacy-key check: the shared step already excludes print-host
keys and maps per-variant values onto the base preset's variant layout.
The --uptodate path and a printer or process given on the command line
are left as they were.
Because the GUI's kept-key set always holds the bookkeeping keys, the
refresh runs for every project that names a system preset, so the CLI
now loads that preset's vendor on every such run.