Add NoGUI frontend based on old SDL frontend + fullscreen UI

src/duckstation-nogui/CMakeLists.txt

@@ -0,0 +1,25 @@
+add_executable(duckstation-nogui
+  imgui_impl_sdl.cpp
+  imgui_impl_sdl.h
+  main.cpp
+  sdl_host_interface.cpp
+  sdl_host_interface.h
+  sdl_key_names.h
+  sdl_util.cpp
+  sdl_util.h
+)
+
+target_include_directories(duckstation-nogui PRIVATE ${SDL2_INCLUDE_DIRS})
+target_link_libraries(duckstation-nogui PRIVATE core common imgui nativefiledialog glad frontend-common scmversion vulkan-loader ${SDL2_LIBRARIES})
+
+if(WIN32)
+  target_sources(duckstation-nogui PRIVATE
+    duckstation-nogui.manifest
+  )
+
+  # We want a Windows subsystem application not console.
+  set_target_properties(duckstation-nogui PROPERTIES
+    WIN32_EXECUTABLE TRUE
+    DEBUG_POSTFIX "-debug")
+endif()
+