build-macos: fix C++20 compatibility for Clang13.1

Fixes compilation on Clang13.1 by backporting some C++20
features that aren't available in Clang and fixing
the CMake config. Note that this doesn't yet properly package
the app nor does anything work at this point.

jthread, stop_token, and condition_variable_any impls taken from
josuttis/jthread and appleCompat.h taken from Citra and modified by me.

src/common/CMakeLists.txt

@@ -186,3 +186,7 @@ if (MSVC)
 else()
   target_link_libraries(common PRIVATE zstd)
 endif()
+
+if (APPLE)
+  target_link_libraries(common PUBLIC range_v3)
+endif()