Functional parity with linux

lib/ruin_app/build.rs

@@ -0,0 +1,18 @@
+use std::env;
+use std::path::PathBuf;
+
+fn main() {
+    println!("cargo:rerun-if-changed=macos/Info.plist");
+
+    let target_os = env::var("CARGO_CFG_TARGET_OS").unwrap_or_default();
+    if target_os != "macos" {
+        return;
+    }
+
+    let manifest_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").expect("manifest dir"));
+    let plist = manifest_dir.join("macos/Info.plist");
+    let arg = format!("-Wl,-sectcreate,__TEXT,__info_plist,{}", plist.display());
+
+    // Ensure all ruin_app executables/examples opt into Retina rendering.
+    println!("cargo:rustc-link-arg-examples={arg}");
+}