Merge branch 'main' into feat/plugin-feature

Resolve five conflicts, all of which needed both sides rather than a pick:

- BackgroundSlicingProcess: ours was a pure tabs->spaces reformat of base, so
  keep main's per-filament volume/nozzle map read-back (its only change here).
- GUI_App: main's #12506 else-if attached to an `if` this branch deleted;
  re-expressed onto the same-agent early-return path (the agent factory caches
  per id, so pointer equality is the same predicate).
- MainFrame: both sides relocated Sync Presets independently; keep main's
  push_notification plus the branch's Plugins menu items.
- Tab: the "TODO: Orca: Support hybrid" blocks were unchanged base, not a branch
  decision; take main's enabled Hybrid to match the already auto-merged siblings.
- test_config: union of both sides' cases (6 plugin + 9 multi-nozzle).

src/slic3r/GUI/BackgroundSlicingProcess.cpp

@@ -233,6 +233,19 @@ void BackgroundSlicingProcess::process_fff()
         if (m_current_plate->get_real_filament_map_mode(preset_bundle.project_config) < FilamentMapMode::fmmManual) {
             std::vector<int> f_maps = m_fff_print->get_filament_maps();
             m_current_plate->set_filament_maps(f_maps);
+            // The engine's concrete per-filament volume assignment is merged into the print
+            // config by the ToolOrdering write-back; reading it back keeps the plate config the
+            // next apply overlays equal to the written-back state (no diff, no re-invalidation)
+            // and persists the auto result (always concrete Std/HF, never the Hybrid seed).
+            std::vector<int> f_volume_maps = m_fff_print->get_filament_volume_maps();
+            m_current_plate->set_filament_volume_maps(f_volume_maps);
+        }
+        if (m_current_plate->get_real_filament_map_mode(preset_bundle.project_config) != FilamentMapMode::fmmNozzleManual) {
+            // The engine-resolved nozzle map is read back for every non-nozzle-manual mode so the
+            // plate config the next apply overlays matches the engine's written-back state
+            // (otherwise the full-config diff would invalidate the g-code on every apply).
+            std::vector<int> f_nozzle_maps = m_fff_print->get_filament_nozzle_maps();
+            m_current_plate->set_filament_nozzle_maps(f_nozzle_maps);
         }
         wxCommandEvent evt(m_event_slicing_completed_id);
         // Post the Slicing Finished message for the G-code viewer to update.
@@ -244,6 +257,9 @@ void BackgroundSlicingProcess::process_fff()
         m_temp_output_path = this->get_current_plate()->get_tmp_gcode_path();
         m_fff_print->export_gcode(m_temp_output_path, m_gcode_result,
                                   [this](const ThumbnailsParams& params) { return this->render_thumbnails(params); });
+        // Orca: BBL printers post-process the g-code in place here and never re-parse it into a fresh
+        // GCodeProcessorResult, so m_gcode_result->nozzle_group_result (consumed by the H2C print-dispatch
+        // nozzle mapping) survives post-processing. No preservation guard is needed on this path.
         if (m_fff_print->is_BBL_printer()) {
             run_post_process_scripts(m_temp_output_path, false, "File", m_temp_output_path, m_fff_print->full_print_config());
         }