set font for local glyph rasterizer GLFW app Apple platforms (#4098)

platform/glfw/glfw_apple_init.mm

@@ -0,0 +1,11 @@
+#import <Foundation/Foundation.h>
+
+// Called early in GLFW initialization so that the local glyph rasterizer
+// can find a suitable CJK font via NSUserDefaults.
+__attribute__((constructor))
+static void setDefaultIdeographicFont() {
+    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
+    if (![defaults objectForKey:@"MLNIdeographicFontFamilyName"]) {
+        [defaults setObject:@[@"PingFang TC"] forKey:@"MLNIdeographicFontFamilyName"];
+    }
+}