The assign_spool endpoint sent wrong MQTT field values for user presets,
causing the slicer's AMS slot detail card to show all fields empty.
Two bugs: (1) cloud API was called with the raw slicer_filament value
including its version suffix (e.g. PFUS9ac902733670a9_07), returning 404;
the silent fallback sent setting_id as tray_info_idx instead of the real
filament_id; (2) no SlotPresetMapping was saved after assignment.
Now strips version suffixes before cloud lookup, resolves the real
filament_id via cloud API (with local preset and generic fallbacks),
includes brand in tray_sub_brands, and saves slot preset mapping.