feat: Init

build/steam/config.vdf

@@ -0,0 +1,21 @@
+"InstallConfigStore"
+{
+        "Software"
+        {
+                "Valve"
+                {
+                        "Steam"
+                        {
+                                "CompatToolMapping"
+                                {
+                                        "0"
+                                        {
+                                                "name"          "proton_experimental"
+                                                "config"                ""
+                                                "priority"              "75"
+                                        }
+                                }
+                        }
+                }
+        }
+}