feat: native Windows ARM64 build support (Snapdragon X Elite) (supersedes #14059) (#14381)

* feat: native Windows ARM64 build support

Builds on the merged DEPS_ARCH=arm64 plumbing (#13424) by adding the
dependency and source fixes needed for a green native ARM64 build on the
windows-11-arm runner. Validated end-to-end on Snapdragon X Elite hardware
(via a downstream fork using the same fixes); see OrcaSlicer/OrcaSlicer#8271
for the full writeup.

Dependencies:
- OpenEXR 2.5.5: ImfSimd.h hard-codes IMF_HAVE_SSE2 for any MSVC, pulling in
  <emmintrin.h> (x86-only) -> C1189. Patch the header to require an x86 target
  and force SSE cache vars off on ARM64.
- Boost.Context: use the winfib implementation on ARM64 (Windows Fiber API)
  to avoid the armasm64 / CMake ASM_ARMASM linker-module bug, while keeping
  the Boost::context target Boost.Asio needs.
- OpenCV: disable WITH_IPP on ARM64 (Intel IPP/IPP-ICV is x86/x64 only;
  otherwise ~200 unresolved ippicv* externals at link).
- OpenSSL: use VC-WIN64-ARM on ARM64.
- FindGLEW: add an ARM64 arch branch.

Sources:
- clipper Int128.hpp: _mul128 is an x64-only intrinsic guarded by _WIN64
  (true on ARM64); guard on _M_X64 and use the portable path.
- imgui imgui_widgets.cpp: fix va_start(vaList, &text) -> va_start(vaList, text)
  (the &-form compiled on x64 but is invalid on ARM64).
- crash reporter: StackWalker.cpp gains an _M_ARM64 branch; BaseException.cpp
  uses Cpsr instead of the x86-only EFlags on ARM64.

CI:
- New build_windows_arm64.yml on windows-11-arm: pins CMake 3.31.x, stages
  ARM64 GMP/MPFR from MSYS2 clangarm64 (with llvm-dlltool import libs),
  caches deps with a fixed-depth hashFiles key, builds and uploads the binary.

OCCT/STEP, SVG-to-3D and text emboss all build and work on ARM64 (no stubs
needed). Full feature parity with x64.

* fix(ci): use forward-slash DESTDIR to avoid CMake '\a' escape error

deps configure failed at GMP/GMP.cmake: "Invalid character escape '\a'"
because DESTDIR carried Windows backslashes (C:\a\...) and is re-parsed
when re-set with the /usr/local suffix. Pass DESTDIR (and the slicer's
DEPS prefix) with forward slashes via %CD:\=/%.

* fix(ci): don't export DESTDIR env var (CMake staged-install doubles paths)

Setting a DESTDIR *environment* variable made CMake treat it as the staged
install prefix and prepend it to every dependency's install path, so e.g.
FreeType installed to <DESTDIR>/a/.../OrcaSlicer_dep/usr/local and OCCT
then couldn't find its headers. Compute the forward-slash path into a
differently-named var (ORCA_DESTDIR) and pass it only via -DDESTDIR.

* ci(windows-arm64): fold ARM64 build into the standard Windows matrix

Replace the standalone build_windows_arm64.yml with a matrix entry on the
existing build_windows job, so x64 and ARM64 share one reusable workflow
chain (build_all -> build_check_cache -> build_deps -> build_orca), per
review feedback on #14059.

- build_all.yml: build_windows now matrices over {x64: windows-latest,
  arm64: windows-11-arm} and threads `arch` through. Self-hosted runner
  stays x64-only.
- build_check_cache.yml: cache key and dep-prefix path are now
  architecture-specific on Windows (deps/build-arm64/OrcaSlicer_dep).
- build_release_vs.bat: accept an `arm64` argument (mirrors
  build_release_vs2022.bat) -> uses `-A ARM64` and the build-arm64 tree.
  The top-level CMake auto-derives CMAKE_PREFIX_PATH from the build dir,
  so no explicit prefix is needed.
- build_deps.yml / build_orca.yml: gate the ARM64-only prep behind
  `inputs.arch == 'arm64'` -- pin CMake 3.31.x, and stage MSYS2
  clangarm64 GMP/MPFR import libs. NSIS installer/PDB/profile_validator
  remain x64-only; ARM64 ships the portable zip. Artifact names get an
  arch suffix to avoid collisions between the two Windows jobs.

https://claude.ai/code/session_0164c7ZhCLsYBmCiVN9pWDjK

* ci(temp): generate GMP/MPFR win-arm64 blobs to commit to repo

* feat(deps): add prebuilt GMP/MPFR win-arm64 blobs

The repo ships prebuilt GMP/MPFR import libs + DLLs for win-x64 and
win-x86; the Windows ARM64 build path copies from win-${DEPS_ARCH}
(CMakeLists.txt) but the win-arm64 blobs were missing, so the slicer
configure failed at "file COPY cannot find .../win-arm64/libgmp-10.dll".

Add win-arm64 libgmp-10.{dll,lib} and libmpfr-4.{dll,lib}, generated from
the MSYS2 clangarm64 gmp/mpfr packages with MSVC-compatible import libs via
llvm-dlltool. Headers are shared across arches and unchanged.

* simplify OpenEXR.cmake

* set default arch

* support msix

* ship installer

* try to fix webview2runtime issue

---------

Co-authored-by: Adam Behrman <adam.behrman@gmail.com>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Adam Behrman <abehrman@users.noreply.github.com>

src/slic3r/GUI/Widgets/WebView.cpp

@@ -77,13 +77,16 @@ DWORD DownloadAndInstallWV2RT() {
   if (downloaded) {
     // Either Package the WebView2 Bootstrapper with your app or download it using fwlink
     // Then invoke install at Runtime.
+    // Keep the path string alive for the duration of the ShellExecuteExW call;
+    // assigning .c_str() of a temporary directly would leave lpFile dangling.
+    const std::wstring installer_path = target_file_path.generic_wstring();
     SHELLEXECUTEINFOW shExInfo = {0};
     shExInfo.cbSize = sizeof(shExInfo);
     shExInfo.fMask = SEE_MASK_NOCLOSEPROCESS;
     shExInfo.hwnd = 0;
     shExInfo.lpVerb = L"runas";
-    shExInfo.lpFile = target_file_path.generic_wstring().c_str();
-    shExInfo.lpParameters = L" /install";
+    shExInfo.lpFile = installer_path.c_str();
+    shExInfo.lpParameters = L" /silent /install";
     shExInfo.lpDirectory = 0;
     shExInfo.nShow = 0;
     shExInfo.hInstApp = 0;
@@ -338,7 +341,11 @@ bool WebView::CheckWebViewRuntime()
 {
     wxWebViewFactoryEdge factory;
     auto wxVersion = factory.GetVersionInfo(wxVersionContext::RunTime);
-    return wxVersion.GetMajor() != 0;
+    bool present = wxVersion.GetMajor() != 0;
+    BOOST_LOG_TRIVIAL(info) << __FUNCTION__ << ": WebView2 runtime "
+                            << (present ? "found, version " : "not found (")
+                            << wxVersion.ToString().ToUTF8().data() << (present ? "" : ")");
+    return present;
 }
 
 bool WebView::DownloadAndInstallWebViewRuntime()