EXPERIMENTAL: Metal backend (#441)

This is not a continuation of the Metal backend; this is simply bringing
the branch up to date and merging it as-is behind an experiment.

---------

Co-authored-by: Isaac Marovitz <isaacryu@icloud.com>
Co-authored-by: Samuliak <samuliak77@gmail.com>
Co-authored-by: SamoZ256 <96914946+SamoZ256@users.noreply.github.com>
Co-authored-by: Isaac Marovitz <42140194+IsaacMarovitz@users.noreply.github.com>
Co-authored-by: riperiperi <rhy3756547@hotmail.com>
Co-authored-by: Gabriel A <gab.dark.100@gmail.com>

src/Ryujinx/Assets/locales.json

@@ -19677,6 +19677,54 @@
         "zh_TW": "選擇模擬器將使用的圖形後端。\n\n只要驅動程式是最新的，Vulkan 對所有現代顯示卡來說都更好用。Vulkan 還能在所有 GPU 廠商上實現更快的著色器編譯 (減少卡頓)。\n\nOpenGL 在舊式 Nvidia GPU、Linux 上的舊式 AMD GPU 或 VRAM 較低的 GPU 上可能會取得更好的效果，不過著色器編譯的卡頓會更嚴重。\n\n如果不確定，請設定為 Vulkan。如果您的 GPU 使用最新的圖形驅動程式也不支援 Vulkan，請設定為 OpenGL。"
       }
     },
+    {
+      "ID": "SettingsTabGraphicsBackendAuto",
+      "Translations": {
+        "ar_SA": "",
+        "de_DE": "",
+        "el_GR": "",
+        "en_US": "Auto",
+        "es_ES": "",
+        "fr_FR": "",
+        "he_IL": "",
+        "it_IT": "",
+        "ja_JP": "",
+        "ko_KR": "",
+        "no_NO": "",
+        "pl_PL": "",
+        "pt_BR": "",
+        "ru_RU": "",
+        "th_TH": "",
+        "tr_TR": "",
+        "uk_UA": "",
+        "zh_CN": "",
+        "zh_TW": ""
+      }
+    },
+    {
+      "ID": "SettingsTabGraphicsBackendAutoTooltip",
+      "Translations": {
+        "ar_SA": "",
+        "de_DE": "",
+        "el_GR": "",
+        "en_US": "Uses Vulkan.\nOn an ARM Mac, and when playing a game that runs well under it, uses the Metal backend.",
+        "es_ES": "",
+        "fr_FR": "",
+        "he_IL": "",
+        "it_IT": "",
+        "ja_JP": "",
+        "ko_KR": "",
+        "no_NO": "",
+        "pl_PL": "",
+        "pt_BR": "",
+        "ru_RU": "",
+        "th_TH": "",
+        "tr_TR": "",
+        "uk_UA": "",
+        "zh_CN": "",
+        "zh_TW": ""
+      }
+    },
     {
       "ID": "SettingsEnableTextureRecompression",
       "Translations": {