feat: Filament Track Switch (H2-series O2L-FTS) support

The Filament Track Switch (H2-series accessory, product code O2L-FTS) feeds
every AMS to both extruders through a two-track switch. Port full support
across the device layer, project config, and GUI.

Device / config:
- Model the switch-aware AMS binding (the set of extruders an AMS can feed
  and which input track A/B feeds it), switch readiness, the O2L-FTS firmware
  module, and the fun2 capability bit for checking a slice against installed
  hardware.
- Register has_filament_switcher and enable_filament_dynamic_map as project
  config that persists with the project and restores from a saved 3mf, and
  force both back to false on every project/printer/CLI load path. Live
  device sync is the only thing that sets them true.

GUI:
- Sidebar sync activates the switch from live device state, attributes each
  AMS to the extruder its input track feeds, shows a floating status icon
  (ready / not-calibrated), and surfaces a one-time tip / not-calibrated
  warning.
- Send dialog gains a non-blocking slice-vs-hardware mismatch warning and a
  blocking error when a slice needs dynamic nozzle mapping but the switch is
  missing or not set up.
- AMS load/unload guards, AMS-view routing glyph + un-calibrated banner +
  hidden external-spool road, and mapping-popup external-spool lockout.
- Filament pickers collapse the per-extruder split into a single deduplicated
  "AMS filaments" group with a smart-assign toggle when the switch is ready.
- Firmware-upgrade panel lists the O2L-FTS accessory and its version.
- Device-provided filament-change steps (ams.cfs) drive the change-step
  display when firmware sends them, including the three switch steps.
- "Load current filament" asks which extruder to feed via a
  FeedDirectionDialog when the switch is calibrated.

Inert without the accessory: every path is gated on the switch being
installed (MQTT aux bit 29, default off) or ready, both project flags default
false, and the per-extruder AMS attribution is byte-identical, so AMS state,
the send/load UI, and sliced g-code are unchanged for every printer that does
not report a Filament Track Switch.

src/slic3r/GUI/SelectMachine.cpp

@@ -1593,6 +1593,58 @@ bool SelectMachineDialog::use_dynamic_nozzle_map() const
     return false;
 }
 
+bool SelectMachineDialog::slicing_with_fila_switch() const
+{
+    if (use_dynamic_nozzle_map())
+        return true;
+
+    if (m_print_type == FROM_NORMAL) {
+        auto has_filament_switcher = wxGetApp().preset_bundle->project_config.option<ConfigOptionBool>("has_filament_switcher");
+        if (has_filament_switcher)
+            return has_filament_switcher->value;
+    } else if (m_print_type == FROM_SDCARD_VIEW) {
+        if (m_required_data_plate_data_list.size() > (size_t) m_print_plate_idx) {
+            auto has_filament_switcher = m_required_data_plate_data_list[m_print_plate_idx]->config.option<ConfigOptionBool>("has_filament_switcher");
+            if (has_filament_switcher)
+                return has_filament_switcher->value;
+        }
+        auto has_filament_switcher = m_required_data_config.option<ConfigOptionBool>("has_filament_switcher");
+        if (has_filament_switcher)
+            return has_filament_switcher->value;
+    }
+    return false;
+}
+
+bool SelectMachineDialog::CheckErrorDynamicSwitchNozzle(MachineObject* obj_)
+{
+    if (!obj_)
+        return false;
+
+    // Advisory only (does not block Send): the file was sliced for a switch state that doesn't
+    // match the installed hardware, so grouping/flush may be suboptimal. Only on firmware that
+    // reports it can check this.
+    if (obj_->is_support_check_track_switch_match_slice_printer && slicing_with_fila_switch() != obj_->GetFilaSwitch()->IsInstalled()) {
+        show_status(PrintDialogStatus::PrintStatusFilaSwitcherSlicingNotMatch,
+                    {_L("The Filament Track Switch installed on the printer does not match the slicing file. Please re-slice to avoid print quality issues.")});
+    }
+
+    // The blocking checks below only matter for dynamic nozzle mapping, which requires a switch.
+    if (!use_dynamic_nozzle_map())
+        return true;
+
+    if (!obj_->GetFilaSwitch()->IsInstalled()) {
+        show_status(PrintDialogStatus::PrintStatusFilaSwitcherError, {_L("This print requires a Filament Track Switch. Please install it first.")});
+        return false;
+    }
+
+    if (!obj_->GetFilaSwitch()->IsReady()) {
+        show_status(PrintDialogStatus::PrintStatusFilaSwitcherError, {_L("The Filament Track Switch has not been setup. Please setup it first.")});
+        return false;
+    }
+
+    return true;
+}
+
 void SelectMachineDialog::clear_nozzle_mapping()
 {
     m_nozzle_mapping_result.clear();
@@ -2010,6 +2062,14 @@ void SelectMachineDialog::show_status(PrintDialogStatus status, std::vector<wxSt
         // Extra-waste warning: allow Send.
         Enable_Refresh_Button(true);
         Enable_Send_Button(true);
+    } else if (status == PrintDialogStatus::PrintStatusFilaSwitcherError) {
+        // Missing or un-set-up switch required by the slice: block Send.
+        Enable_Refresh_Button(true);
+        Enable_Send_Button(false);
+    } else if (status == PrintDialogStatus::PrintStatusFilaSwitcherSlicingNotMatch) {
+        // Advisory slicing/hardware mismatch: allow Send.
+        Enable_Refresh_Button(true);
+        Enable_Send_Button(true);
     }
 
     /*enter perpare mode*/
@@ -3795,6 +3855,10 @@ void SelectMachineDialog::update_show_status(MachineObject* obj_)
         }
     }
 
+    // Filament Track Switch: warn on a slicing/hardware mismatch, and block Send when dynamic
+    // nozzle mapping needs a switch that isn't installed or set up. No-op for printers without one.
+    if (!CheckErrorDynamicSwitchNozzle(obj_)) return;
+
     // Rack print-dispatch nozzle mapping (dynamic V1): request/await the printer's mapping and block
     // Send while it computes. No-op for non-rack printers.
     if (!CheckErrorSyncNozzleMappingResultV1(obj_)) return;