Re-added WinRT support until we're sure that it's no longer being used

cmake/test/CMakeLists.txt

@@ -29,7 +29,7 @@ add_feature_info("TEST_STATIC" TEST_STATIC "Test linking with static library")
 
 if(TEST_SHARED)
     find_package(SDL3 REQUIRED CONFIG COMPONENTS SDL3)
-    if(EMSCRIPTEN OR WIN32)
+    if(EMSCRIPTEN OR (WIN32 AND NOT WINDOWS_STORE))
         find_package(SDL3 REQUIRED CONFIG COMPONENTS SDL3main)
     endif()
     add_executable(gui-shared WIN32 main_gui.c)
@@ -79,7 +79,7 @@ endif()
 
 if(TEST_STATIC)
     find_package(SDL3 REQUIRED CONFIG COMPONENTS SDL3-static)
-    if(EMSCRIPTEN OR WIN32)
+    if(EMSCRIPTEN OR (WIN32 AND NOT WINDOWS_STORE))
         find_package(SDL3 REQUIRED CONFIG COMPONENTS SDL3main)
     endif()
     add_executable(gui-static WIN32 main_gui.c)