feat: implementation of gsl::dyn_array (#1228)

* feat: implementation of gsl::dyn_array

Implement gsl::dyn_array<T, Allocator> as specified by the
CppCoreGuidlines here:
https://github.com/isocpp/CppCoreGuidelines/blob/master/docs/dyn_array.md

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

.github/workflows/compilers.yml

@@ -77,23 +77,30 @@ jobs:
           cmake_preset: clang-${{ matrix.cxx_version }}-${{ matrix.build_type == 'Debug' && 'debug' || 'release' }}
           extra_cmake_configure_args: '-DCMAKE_CXX_FLAGS="-isysroot \"$(xcode-select --print-path)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk\""'
 
-  VisualStudio:
+  msvc:
     strategy:
       matrix:
-        generator: [ 'Visual Studio 17 2022' ]
         image: [ windows-2022, windows-2025 ]
         build_type: [ Debug, Release ]
-        extra_args: [ '', '-T ClangCL' ]
+        toolset: [ 'msvc', 'ClangCL' ]
         cxx_version: [ 14, 17, 20, 23 ]
+        include:
+          # Regular MSVC builds use Ninja (from preset)
+          - toolset: 'msvc'
+            generator_override: ''
+          # ClangCL builds require Visual Studio generator
+          - toolset: 'ClangCL'
+            generator_override: '-G "Visual Studio 17 2022" -T ClangCL'
     runs-on: ${{ matrix.image }}
     steps:
       - uses: actions/checkout@v6
       - uses: microsoft/setup-msbuild@v3
+      - uses: ilammy/msvc-dev-cmd@v1
 
       - name: Run CMake (configure, build, test)
         uses: ./.github/workflows/cmake
         with:
           cmake_preset: msvc-${{ matrix.cxx_version }}-${{ matrix.build_type == 'Debug' && 'debug' || 'release' }}
-          extra_cmake_configure_args: ${{ matrix.extra_args }}
-          extra_cmake_build_args: --config ${{ matrix.build_type }}
-          extra_ctest_args: -C ${{ matrix.build_type }}
+          extra_cmake_configure_args: ${{ matrix.generator_override }}
+          extra_cmake_build_args: ${{ matrix.toolset == 'ClangCL' && format('--config {0}', matrix.build_type) || '' }}
+          extra_ctest_args: ${{ matrix.toolset == 'ClangCL' && format('-C {0}', matrix.build_type) || '' }}