use of CMAKE_BUILD_TYPE to set compiler options/defines is incompatible with multi-config generators

[abdes]

See Build Configurations for more details.

In several places, there is still code that checks CMAKE_BUILD_TYPE to set specific compiler flags or defines. Such code is problematic:

Generator expressions should be used instead to handle configuration-specific logic correctly, regardless of the generator used. For example:

# Works correctly for both single and multi-config generators
target_compile_definitions(exe1 PRIVATE
  $<$<CONFIG:Debug>:DEBUG_BUILD>
)