get the metal backend to compile (does not load)

projects/apis/metal/loader/metal_command_loader.c

@@ -0,0 +1,22 @@
+#include "metal_loader.h"
+
+gnCommandFunctions loadMetalCommandFunctions() {
+    return (gnCommandFunctions){
+        ._gnCommandPoolAllocateCommandBuffers = NULL,
+        ._gnBeginCommandBuffer = NULL,
+        ._gnResetCommandBuffer = NULL,
+        ._gnEndCommandBuffer = NULL,
+
+        ._gnCommandBeginRenderPass = NULL,
+        ._gnCommandEndRenderPass = NULL,
+        ._gnCommandBindGraphicsPipeline = NULL,
+        ._gnCommandSetViewport = NULL,
+        ._gnCommandSetScissor = NULL,
+        ._gnCommandBindUniform = NULL,
+        ._gnCommandPushConstant = NULL,
+
+        ._gnCommandBindBuffer = NULL,
+        ._gnCommandDraw = NULL,
+        ._gnCommandDrawIndexed = NULL,
+    };
+}