feat(launcher): build executable to require administrator by default

Add rustc-link-arg directives in build.rs to embed a UAC manifest:
- /MANIFEST:EMBED
- /MANIFESTUAC:level='requireAdministrator'

launcher/build.rs

@@ -0,0 +1,4 @@
+fn main() {
+    println!("cargo:rustc-link-arg-bin=launcher=/MANIFEST:EMBED");
+    println!("cargo:rustc-link-arg-bin=launcher=/MANIFESTUAC:level=\'requireAdministrator\'");
+}