cmake: Add application manifests when cross-compiling for Windows

Windows application manifests provide several benefits. However, on the
master branch, the linker generates and embeds manifests only when
building with MSVC.

This change unifies manifest embedding for both native and
cross-compilation.

cmake/module/AddWindowsResources.cmake

@@ -4,11 +4,24 @@
 
 include_guard(GLOBAL)
 
-macro(add_windows_resources target rc_file)
+function(add_windows_resources target rc_file)
   if(WIN32)
     target_sources(${target} PRIVATE ${rc_file})
     set_property(SOURCE ${rc_file}
       APPEND PROPERTY COMPILE_DEFINITIONS WINDRES_PREPROC
     )
   endif()
-endmacro()
+endfunction()
+
+# Add a fusion manifest to Windows executables.
+# See: https://learn.microsoft.com/en-us/windows/win32/sbscs/application-manifests
+function(add_windows_application_manifest target)
+  if(WIN32)
+    configure_file(${PROJECT_SOURCE_DIR}/cmake/windows-app.manifest.in ${target}.manifest USE_SOURCE_PERMISSIONS)
+    file(CONFIGURE
+      OUTPUT ${target}-manifest.rc
+      CONTENT "1 /* CREATEPROCESS_MANIFEST_RESOURCE_ID */ 24 /* RT_MANIFEST */ \"${target}.manifest\""
+    )
+    add_windows_resources(${target} ${CMAKE_CURRENT_BINARY_DIR}/${target}-manifest.rc)
+  endif()
+endfunction()