Merge upstream/main into belt-printer

Brings belt-printer up to main 4b4a261787. Resolutions:

- G-code header (#15897, #15915): main moved the header, config and
  thumbnail block later in _do_export; write_belt_header() moves with it,
  still after the thumbnails and outside the BTT_TFT gate.
- _extrude: first-layer acceleration keeps the per-path first-layer plane
  test with main's cached nozzle index (#16028); main's set_speed out-param
  form (#16108) everywhere else.
- GCodeWriter (#16108): the arc-to-polyline fallback for machine mappings
  that cannot express G2/G3 now runs in the out-param extrude_arc_to_xy,
  which is the overload GCode calls, and appends to the caller's string.
- GCodeProcessorResult: the belt fields join main's forwarding assign.
- Clipper2 (#15969): belt arrange helpers take Slic3r::Point; the tree
  support join types lose their ClipperLib qualifier.
- CLI arrange (#15837): belt printers still reserve no wipe tower.
- Wipe tower options (#15841): the two new sparse-layer toggles are hidden
  for belt printers like the rest of the tower options.
- Keyboard shortcuts (#15706): main's registry replaces the old key switch;
  the belt view toggle is re-registered in the next commit.
- Print::process: the belt purge-plan undo runs before main's SliceStarted
  event.
- scripts/filament_id_snapshot.json: deleted on main (a77209af8f).
- Includes and appended tests: union of both sides.

src/libslic3r/Arrange.cpp

@@ -1,9 +1,28 @@
 #include "Arrange.hpp"
+#include "ExPolygon.hpp"
+#include "Point.hpp"
 #include "Print.hpp"
 #include "BoundingBox.hpp"
+#include "PrintConfig.hpp"
 #include "libslic3r.h"
 
+#include <Eigen/Core>
+#include <boost/geometry/index/parameters.hpp>
+#include <functional>
+#include <algorithm>
+#include <cstdlib>
+#include <cmath>
+#include <cstddef>
+#include <boost/geometry/algorithms/convert.hpp>
+#include <array>
+#include <boost/geometry/index/predicates.hpp>
+#include <iterator>
+#include <exception>
 #include <libnest2d/backends/libslic3r/geometries.hpp>
+#include "libnest2d/common.hpp"
+#include "libnest2d/geometry_traits_nfp.hpp"
+#include "libnest2d/nester.hpp"
+#include "libnest2d/geometry_traits.hpp"
 #include <libnest2d/optimizers/nlopt/subplex.hpp>
 #include <libnest2d/placers/nfpplacer.hpp>
 #include <libnest2d/selections/firstfit.hpp>
@@ -13,6 +32,11 @@
 #include <ClipperUtils.hpp>
 
 #include <boost/geometry/index/rtree.hpp>
+#include <utility>
+#include <vector>
+#include <tuple>
+#include <set>
+#include <string>
 
 #if defined(_MSC_VER) && defined(__clang__)
 #define BOOST_NO_CXX17_HDR_STRING_VIEW
@@ -55,7 +79,7 @@ namespace Slic3r {
 
 template<class Tout = double, class = FloatingOnly<Tout>, int...EigenArgs>
 inline constexpr Eigen::Matrix<Tout, 2, EigenArgs...> unscaled(
-    const Slic3r::ClipperLib::IntPoint &v) noexcept
+    const Slic3r::Point &v) noexcept
 {
     return Eigen::Matrix<Tout, 2, EigenArgs...>{unscaled<Tout>(v.x()),
                                                 unscaled<Tout>(v.y())};
@@ -411,7 +435,7 @@ protected:
         // 2) X distance of item corner to bed corner (low weight)
         // 3) item row occupancy (useful when rotation is enabled)
         // 4）需要允许往屏蔽区域的左边或下边去一点，不然很多物体可能认为摆不进去，实际上我们最后是可以做平移的
-    double dist_for_BOTTOM_LEFT(Box ibb, const ClipperLib::IntPoint& origin_pack)
+    double dist_for_BOTTOM_LEFT(Box ibb, const Slic3r::Point& origin_pack)
     {
         double dist_corner_y = ibb.minCorner().y() - origin_pack.y();
         double dist_corner_x = ibb.minCorner().x() - origin_pack.x();
@@ -466,12 +490,12 @@ protected:
         return norm(d);
     }
 
-    double corner_bindist(const Box &ibb, const ClipperLib::IntPoint &origin_pack)
+    double corner_bindist(const Box &ibb, const Slic3r::Point &origin_pack)
     {
         return params.is_belt ? dist_along_belt(ibb) : dist_for_BOTTOM_LEFT(ibb, origin_pack);
     }
 
-        double dist_to_bin(const Box& ibb, const ClipperLib::IntPoint& origin_pack, typename Packer::PlacementConfig::Alignment starting_point_alignment)
+    double dist_to_bin(const Box& ibb, const Slic3r::Point& origin_pack, typename Packer::PlacementConfig::Alignment starting_point_alignment)
     {
         double bindist = 0;
         if (starting_point_alignment == PConfig::Alignment::BOTTOM_LEFT)
@@ -489,7 +513,7 @@ protected:
     // as it possibly can be but at the same time, it has to provide
     // reasonable results.
     std::tuple<double /*score*/, Box /*farthest point from bin center*/>
-    objfunc(const Item &item, const ClipperLib::IntPoint &origin_pack)
+    objfunc(const Item &item, const Slic3r::Point &origin_pack)
     {
         const double bin_area = m_bin_area;
         const SpatIndex& spatindex = m_rtree;
@@ -1087,7 +1111,12 @@ void _arrange(
 inline Box to_nestbin(const BoundingBox &bb) { return Box{{bb.min(X), bb.min(Y)}, {bb.max(X), bb.max(Y)}};}
 inline Circle to_nestbin(const CircleBed &c) { return Circle({c.center()(0), c.center()(1)}, c.radius()); }
 inline ExPolygon to_nestbin(const Polygon &p) { return ExPolygon{p}; }
-inline Box to_nestbin(const InfiniteBed &bed) { return Box::infinite({bed.center.x(), bed.center.y()}); }
+// libnest2d's infinite box reaches the int64 limit, where Clipper2's double math is no longer exact.
+inline Box to_nestbin(const InfiniteBed &bed)
+{
+    const coord_t r = coord_t(1) << 50;
+    return Box{{bed.center.x() - r, bed.center.y() - r}, {bed.center.x() + r, bed.center.y() + r}};
+}
 
 inline coord_t width(const BoundingBox& box) { return box.max.x() - box.min.x(); }
 inline coord_t height(const BoundingBox& box) { return box.max.y() - box.min.y(); }
@@ -1195,8 +1224,6 @@ void arrange(ArrangePolygons &      arrangables,
              const BedT &           bed,
              const ArrangeParams &  params)
 {
-    namespace clppr = Slic3r::ClipperLib;
-
     std::vector<Item> items, fixeditems;
     items.reserve(arrangables.size());