Switch Windows build configuration from GCC to MSVC and update CMake to use clang-cl

Updated Windows build environment to use MSVC with ccache and clang-cl as the compiler. Adjusted CMake settings and environment variables to reflect the new toolchain. Simplified build configuration by removing GCC-specific setup.

Author: allnes

.github/workflows/main.yml

@@ -851,30 +851,29 @@ jobs:
       - name: Setup ccache
         uses: Chocobo1/setup-ccache-action@v1
         with:
-          windows_compile_environment: gcc
+          windows_compile_environment: msvc
 
       - name: Setup ninja
         uses: seanmiddleditch/gha-setup-ninja@v6
 
       - name: CMake configure
         run: >
           cmake -S . -B build -G Ninja
-          -D CMAKE_C_COMPILER=clang
-          -D CMAKE_CXX_COMPILER=clang++
+          -D CMAKE_C_COMPILER=clang-cl
+          -D CMAKE_CXX_COMPILER=clang-cl
           -D CMAKE_C_COMPILER_LAUNCHER=ccache
           -D CMAKE_CXX_COMPILER_LAUNCHER=ccache
           -D CMAKE_BUILD_TYPE=Release
           -D CMAKE_INSTALL_PREFIX=install
-          -D CMAKE_PREFIX_PATH="${{ env.MPICH_ROOT }}"
         env:
-          CC: clang
-          CXX: clang++
+          CC: clang-cl
+          CXX: clang-cl
 
       - name: Build project
         run: cmake --build build --config Release --parallel
         env:
-          CC: clang
-          CXX: clang++
+          CC: clang-cl
+          CXX: clang-cl
 
       - name: Install project
         run: cmake --install build