Toolchange Cyclic Order (#14868)

* Toolchange Cyclic Order

* Apply cyclic order to first layer

* Unit test

* Copilot fixes

---------

Co-authored-by: Rodrigo Faselli <162915171+RF47@users.noreply.github.com>

src/libslic3r/PrintConfig.cpp

@@ -6700,6 +6700,34 @@ void PrintConfigDef::init_fff_params()
     def->enum_labels.emplace_back(L("Cyclic"));
     def->set_default_value(new ConfigOptionEnum<ToolChangeOrderingType>(ToolChangeOrderingType::Default));
 
+    def = this->add("toolchange_cyclic_order", coString);
+    def->label = L("Cyclic order");
+    def->category = L("Advanced");
+    def->tooltip = L(
+        "Custom filament sequence used by the cyclic toolchange ordering, as filament numbers separated by commas (e.g. \"3,2,1,4\").\n"
+        "Each layer prints its filaments following this sequence; filaments not listed are printed last, in ascending order.\n"
+        "Leave empty to cycle through the filaments in ascending order."
+    );
+    def->mode = comExpert;
+    def->set_default_value(new ConfigOptionString(""));
+
+    def = this->add("toolchange_cyclic_first_layer", coBool);
+    def->label = L("Apply cyclic order to first layer");
+    def->category = L("Advanced");
+    def->tooltip = L(
+        "Applies the cyclic toolchange order to the first layer as well.\n"
+        "By default this is disabled, because the first layer is instead ordered for the best bed "
+        "adhesion: filaments that print small, fragile first-layer features are printed last, so the "
+        "following tool changes and travel moves are less likely to knock those weakly anchored parts "
+        "loose. This first-layer order also honors a custom first layer filament sequence when one is set. "
+        "The cyclic order's benefit (extra tool changes give each layer more time to cool) does not apply "
+        "to the first layer, which is printed slowly and hot for adhesion.\n"
+        "Enable this only if you need the exact same tool sequence on every layer, including the first, at "
+        "the cost of that adhesion optimization."
+    );
+    def->mode = comExpert;
+    def->set_default_value(new ConfigOptionBool(false));
+
     def = this->add("slice_closing_radius", coFloat);
     def->label = L("Slice gap closing radius");
     def->category = L("Quality");