Fix Windows CI

[TealSeer]

Changes in the windows-2025 image caused Windows CI jobs to start failing, there was two problems to be fixed:

• MSVC builds started complaining that nmake couldn't be found, this was fixed by adding a build step that sets the environment variables you'd get if you ran the VS Developer Command Prompt
• ClangCL builds were complaining that the NMake generator doesn't support toolset specification, fixed by changing the generator to Ninja and explicitly passing DCMAKE_C/CXX_COMPILER flags instead of -T

[eXpl0it3r]

Both these issues can be fixed by updating CMake to a newer version on Windows.

The issue is that the selected version of CMake doesn't know about the VS 2026 generator and thus fallsback to the NMake generator.

The issue arises with the new image, as VS 2026 was introduced replacing VS 2022.

I recently fixed this for SFML itself.

[TealSeer]

Both these issues can be fixed by updating CMake to a newer version on Windows.

The issue is that the selected version of CMake doesn't know about the VS 2026 generator and thus fallsback to the NMake generator.

The issue arises with the new image, as VS 2026 was introduced replacing VS 2022.

I recently fixed this for SFML itself.

I'm currently experimenting with this on another branch, just bumping the CMake version for Windows runners caused the build to fail, seemingly because the FreeType version depended on CMake 3, that required bumping SFML itself from 3.0 to 3.1 which turned it from what I thought would be a simple fix into a Whole Thing.

EDIT: After playing with it some, I can get CI to pass after bumping CMake and SFML, but it requires #343 to be merged (the build errors are warnings about deprecation being treated as errors). So maybe something to look into after that's done, I'll attach the patch file for posterity.
bump.patch