Expose lightning infill angles (#13848)

* expose lightning infill angles

Update PrintObject.cpp

* Update src/libslic3r/PrintConfig.cpp

* Apply suggestions from code review

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* Update GUI_Factories.cpp

* Fix lightning infill angles to 45 degrees for supports

Updated lightning infill angles to fixed values for consistency.

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Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

src/libslic3r/PrintConfig.cpp

@@ -3047,6 +3047,36 @@ void PrintConfigDef::init_fff_params()
     def->mode     = comAdvanced;
     def->set_default_value(new ConfigOptionFloat(60));
 
+    def           = this->add("lightning_overhang_angle", coFloat);
+    def->label    = L("Lightning overhang angle");
+    def->category = L("Strength");
+    def->tooltip  = L("Maximum overhang angle for Lightning infill support propagation.");
+    def->sidetext = u8"°";
+    def->min      = 5;
+    def->max      = 85;
+    def->mode     = comExpert;
+    def->set_default_value(new ConfigOptionFloat(45));
+
+    def           = this->add("lightning_prune_angle", coFloat);
+    def->label    = L("Prune angle");
+    def->category = L("Strength");
+    def->tooltip  = L("Controls how aggressively short or unsupported Lightning branches are pruned. This angle is converted internally to a per-layer distance.");
+    def->sidetext = u8"°";
+    def->min      = 5;
+    def->max      = 85;
+    def->mode     = comExpert;
+    def->set_default_value(new ConfigOptionFloat(45));
+
+    def           = this->add("lightning_straightening_angle", coFloat);
+    def->label    = L("Straightening angle");
+    def->category = L("Strength");
+    def->tooltip  = L("Maximum straightening angle used to simplify Lightning branches.");
+    def->sidetext = u8"°";
+    def->min      = 5;
+    def->max      = 85;
+    def->mode     = comExpert;
+    def->set_default_value(new ConfigOptionFloat(45));
+
     auto def_infill_anchor_min = def = this->add("infill_anchor", coFloatOrPercent);
     def->label = L("Sparse infill anchor length");
     def->category = L("Strength");