[aceRage]

What

The per-filament slot dropdown in the third-party send dialogs ("Filament 1 PLA -> Tray 2 PLA Generic") is replaced by a Bambu-send-dialog-style swatch map: one MaterialItem card per used filament (slicer colour on top, device slot colour underneath, badge), and a MappingItem tile popup grouped by unit with an "As sliced" tile. The Bambu SelectMachineDialog is unchanged.

It is now the picker for every PrintHostSendDialog host that reports named slots:

Host	Slots	Tile labels	Starting slot
Elegoo CC1 + CANVAS	CANVAS trays	1A..1D (2A.. for a second unit)	remembered mapping (preselect_slot), else closest colour
Snapmaker U1	toolheads (print_task_config)	T1..T4	closest colour
QIDI Box (#611)	Box slots b*4+n	1A..1D, 2A..	the filament's own material first, closest colour among those, never colour alone
No slots / no filament names	none	no rows, dialog as before	-
Flashforge	its own IFS dialog	unchanged	unchanged

Tile labels (fix for the review finding)

Labels come from the slot's position, never the printer's raw ids (third_party_slots_from):

• CANVAS: units are numbered in order of appearance and trays by their place in the unit. A 1-based tray_id or canvas_id no longer reads B, C, D, A or 2A.
• QIDI Box: Box slot b*4+n is <b+1><A+n>.
• Tool slots (unit = -1, U1 / Moonraker toolheads): T1..T4, as Slot::label() and the Device card name them.
• Slot::index stays the value the mapping string and the remembered mapping use.

Kept as before

• Auto-match: initial_slot_position() uses the remembered slot first, else PrintHostDevices::auto_match_slot(..., qidi_box). That is the same rule the wxChoice rows used.
• Elegoo remembered mappings: preselect_slot, remember on send, and slot_map_for all still read mapping_choice_positions().
• Warnings:
  • The Elegoo warnings (more filaments than trays, temperature out of range, empty tray, shared tray) keep their original msgids, so existing translations still apply. They now name the tray by its tile label ("tray 1B").
  • Type and colour mismatch lines are added under the map.
  • With no rows there are no warnings, the same guard as before.
• QIDI: the options panel and the printing guard are unchanged. Use Box off greys the map and sends no mapping.
• Nozzle badges follow filament_map only when the device's slots say which nozzle they feed. A U1, whose filament_map may name toolheads, shows filament numbers.
• Light/dark theme and DPI: the panel's sys_color_changed and msw_rescale handlers are called from the dialog.

Tests

tests/slic3rutils/third_party_filament_map_tests.cpp (new; the PR's model tests were moved out of the Elegoo file):

• Labels per host kind: CANVAS with 0-based and 1-based trays, a 1-based unit and two units; U1 T1..T4; QIDI one and two Boxes.
• Auto-match per host kind: U1/CANVAS closest colour; QIDI material-first, an unloaded slot, no type, and the same slots treated as a non-Box host.
• Remembered CANVAS mapping beats the colour match and encodes to the protocol index.
• Encode, read-only identity, mismatch and badges. The badge cases include U1 with a multi-nozzle filament_map.

Builds

• Windows: edgebuild job 342 (swatch). It runs slic3rutils_tests, installs a test copy at C:/Dev/EdgeSlicerTest/swatch and runs the G-code gate. Result: succeeded on the VM; slic3rutils_tests all passed (1324 cases, the 10 new map cases included); G-code gate IDENTICAL 10/10 vs the Windows baseline 6b47212.
• Mac: edgebuild job 341 (swatch_mac, --app). slic3rutils_tests: all passed (1337 cases). Test copy at ~/EdgeSlicerTest/swatch_mac/EdgeSlicer.app.

Hand test

• CC1 Upload and Print: swatches labelled 1A..1D in tray order. Send once with a non-default pick, reopen, and check that the remembered pick is preselected. Warnings read "tray 1B" etc.
• U1 send dialog: T1..T4 swatches with the right colours; an empty head shows -. Badges show filament numbers.
• QIDI Box: code review only (no printer).
• A host with no slots (plain OctoPrint/Moonraker without filament names) looks unchanged.
• Light/dark theme switch with the dialog open; popup open then close dialog.
• Mac copy: same CC1/U1 glance.

Draft until the owner's hand test. No printer was contacted by the agent.