Building the renderer on Windows (CauldronGPU.Setup.Platform): MSVC's C++ tools, SDL3's
development files, Vulkan's headers, and a Vulkan driver to run it.
MSVC is found with Microsoft's vswhere.exe, and the environment its vcvars64.bat sets
is kept in the configuration, so builds work from any command prompt. SDL3 is looked for
in SDL3_DIR, the setup's folder, C:\SDL3* and the Downloads folder; Vulkan's headers
in VULKAN_INCLUDE, VULKAN_SDK, C:\VulkanSDK\<version> and the setup's folder. SDL3
and the headers are downloaded into the setup's folder when missing, which needs no
administrator rights; the renderer loads the driver's vulkan-1.dll when it runs.
MSVC's Build Tools are installed with winget, which asks for administrator rights.